Opcodes

Ops have a 'cost' of 1 unless otherwise specified.

err

• Opcode: 0x00
• Stack: ... → exits
• Fail immediately.

sha256

• Opcode: 0x01
• Stack: ..., A: []byte → ..., []byte
• SHA256 hash of value A, yields [32]byte
• Cost:
  • 7 (v1)
  • 35 (since v2)

keccak256

• Opcode: 0x02
• Stack: ..., A: []byte → ..., []byte
• Keccak256 hash of value A, yields [32]byte
• Cost:
  • 26 (v1)
  • 130 (since v2)

sha512_256

• Opcode: 0x03
• Stack: ..., A: []byte → ..., []byte
• SHA512_256 hash of value A, yields [32]byte
• Cost:
  • 9 (v1)
  • 45 (since v2)

ed25519verify

• Opcode: 0x04
• Stack: ..., A: []byte, B: []byte, C: []byte → ..., uint64
• for (data A, signature B, pubkey C) verify the signature of ("ProgData" || program_hash || data) against the pubkey => {0 or 1}
• Cost: 1900

The 32 byte public key is the last element on the stack, preceded by the 64 byte signature at the second-to-last element on the stack, preceded by the data which was signed at the third-to-last element on the stack.

ecdsa_verify v

• Opcode: 0x05 {uint8 curve index}
• Stack: ..., A: []byte, B: []byte, C: []byte, D: []byte, E: []byte → ..., uint64
• for (data A, signature B, C and pubkey D, E) verify the signature of the data against the pubkey => {0 or 1}
• Cost: Secp256k1=1700 Secp256r1=2500
• Availability: v5

ECDSA Curves:

Index	Name	In	Notes
0	Secp256k1		secp256k1 curve, used in Bitcoin
1	Secp256r1	v7	secp256r1 curve, NIST standard

The 32 byte Y-component of a public key is the last element on the stack, preceded by X-component of a pubkey, preceded by S and R components of a signature, preceded by the data that is fifth element on the stack. All values are big-endian encoded. The signed data must be 32 bytes long, and signatures in lower-S form are only accepted.

ecdsa_pk_decompress v

• Opcode: 0x06 {uint8 curve index}
• Stack: ..., A: []byte → ..., X: []byte, Y: []byte
• decompress pubkey A into components X, Y
• Cost: Secp256k1=650 Secp256r1=2400
• Availability: v5

The 33 byte public key in a compressed form to be decompressed into X and Y (top) components. All values are big-endian encoded.

ecdsa_pk_recover v

• Opcode: 0x07 {uint8 curve index}
• Stack: ..., A: []byte, B: uint64, C: []byte, D: []byte → ..., X: []byte, Y: []byte
• for (data A, recovery id B, signature C, D) recover a public key
• Cost: 2000
• Availability: v5

S (top) and R elements of a signature, recovery id and data (bottom) are expected on the stack and used to deriver a public key. All values are big-endian encoded. The signed data must be 32 bytes long.

+

• Opcode: 0x08
• Stack: ..., A: uint64, B: uint64 → ..., uint64
• A plus B. Fail on overflow.

Overflow is an error condition which halts execution and fails the transaction. Full precision is available from addw.

-

• Opcode: 0x09
• Stack: ..., A: uint64, B: uint64 → ..., uint64
• A minus B. Fail if B > A.

/

• Opcode: 0x0a
• Stack: ..., A: uint64, B: uint64 → ..., uint64
• A divided by B (truncated division). Fail if B == 0.

divmodw is available to divide the two-element values produced by mulw and addw.

*

• Opcode: 0x0b
• Stack: ..., A: uint64, B: uint64 → ..., uint64
• A times B. Fail on overflow.

Overflow is an error condition which halts execution and fails the transaction. Full precision is available from mulw.

<

• Opcode: 0x0c
• Stack: ..., A: uint64, B: uint64 → ..., uint64
• A less than B => {0 or 1}

>

• Opcode: 0x0d
• Stack: ..., A: uint64, B: uint64 → ..., uint64
• A greater than B => {0 or 1}

<=

• Opcode: 0x0e
• Stack: ..., A: uint64, B: uint64 → ..., uint64
• A less than or equal to B => {0 or 1}

>=

• Opcode: 0x0f
• Stack: ..., A: uint64, B: uint64 → ..., uint64
• A greater than or equal to B => {0 or 1}

&&

• Opcode: 0x10
• Stack: ..., A: uint64, B: uint64 → ..., uint64
• A is not zero and B is not zero => {0 or 1}

||

• Opcode: 0x11
• Stack: ..., A: uint64, B: uint64 → ..., uint64
• A is not zero or B is not zero => {0 or 1}

==

• Opcode: 0x12
• Stack: ..., A, B → ..., uint64
• A is equal to B => {0 or 1}

!=

• Opcode: 0x13
• Stack: ..., A, B → ..., uint64
• A is not equal to B => {0 or 1}

!

• Opcode: 0x14
• Stack: ..., A: uint64 → ..., uint64
• A == 0 yields 1; else 0

len

• Opcode: 0x15
• Stack: ..., A: []byte → ..., uint64
• yields length of byte value A

itob

• Opcode: 0x16
• Stack: ..., A: uint64 → ..., []byte
• converts uint64 A to big-endian byte array, always of length 8

btoi

• Opcode: 0x17
• Stack: ..., A: []byte → ..., uint64
• converts big-endian byte array A to uint64. Fails if len(A) > 8. Padded by leading 0s if len(A) < 8.

btoi fails if the input is longer than 8 bytes.

%

• Opcode: 0x18
• Stack: ..., A: uint64, B: uint64 → ..., uint64
• A modulo B. Fail if B == 0.

|

• Opcode: 0x19
• Stack: ..., A: uint64, B: uint64 → ..., uint64
• A bitwise-or B

&

• Opcode: 0x1a
• Stack: ..., A: uint64, B: uint64 → ..., uint64
• A bitwise-and B

^

• Opcode: 0x1b
• Stack: ..., A: uint64, B: uint64 → ..., uint64
• A bitwise-xor B

~

• Opcode: 0x1c
• Stack: ..., A: uint64 → ..., uint64
• bitwise invert value A

mulw

• Opcode: 0x1d
• Stack: ..., A: uint64, B: uint64 → ..., X: uint64, Y: uint64
• A times B as a 128-bit result in two uint64s. X is the high 64 bits, Y is the low

addw

• Opcode: 0x1e
• Stack: ..., A: uint64, B: uint64 → ..., X: uint64, Y: uint64
• A plus B as a 128-bit result. X is the carry-bit, Y is the low-order 64 bits.
• Availability: v2

divmodw

• Opcode: 0x1f
• Stack: ..., A: uint64, B: uint64, C: uint64, D: uint64 → ..., W: uint64, X: uint64, Y: uint64, Z: uint64
• W,X = (A,B / C,D); Y,Z = (A,B modulo C,D)
• Cost: 20
• Availability: v4

The notation J,K indicates that two uint64 values J and K are interpreted as a uint128 value, with J as the high uint64 and K the low.

intcblock uint ...

• Opcode: 0x20 {varuint length} [{varuint value}, ...]
• Stack: ... → ...
• prepare block of uint64 constants for use by intc

intcblock loads following program bytes into an array of integer constants in the evaluator. These integer constants can be referred to by intc and intc_* which will push the value onto the stack. Subsequent calls to intcblock reset and replace the integer constants available to the script.

intc i

• Opcode: 0x21 {uint8 int constant index}
• Stack: ... → ..., uint64
• Ith constant from intcblock

intc_0

• Opcode: 0x22
• Stack: ... → ..., uint64
• constant 0 from intcblock

intc_1

• Opcode: 0x23
• Stack: ... → ..., uint64
• constant 1 from intcblock

intc_2

• Opcode: 0x24
• Stack: ... → ..., uint64
• constant 2 from intcblock

intc_3

• Opcode: 0x25
• Stack: ... → ..., uint64
• constant 3 from intcblock

bytecblock bytes ...

• Opcode: 0x26 {varuint length} [({varuint value length} bytes), ...]
• Stack: ... → ...
• prepare block of byte-array constants for use by bytec

bytecblock loads the following program bytes into an array of byte-array constants in the evaluator. These constants can be referred to by bytec and bytec_* which will push the value onto the stack. Subsequent calls to bytecblock reset and replace the bytes constants available to the script.

bytec i

• Opcode: 0x27 {uint8 byte constant index}
• Stack: ... → ..., []byte
• Ith constant from bytecblock

bytec_0

• Opcode: 0x28
• Stack: ... → ..., []byte
• constant 0 from bytecblock

bytec_1

• Opcode: 0x29
• Stack: ... → ..., []byte
• constant 1 from bytecblock

bytec_2

• Opcode: 0x2a
• Stack: ... → ..., []byte
• constant 2 from bytecblock

bytec_3

• Opcode: 0x2b
• Stack: ... → ..., []byte
• constant 3 from bytecblock

arg n

• Opcode: 0x2c {uint8 arg index N}
• Stack: ... → ..., []byte
• Nth LogicSig argument
• Mode: Signature

arg_0

• Opcode: 0x2d
• Stack: ... → ..., []byte
• LogicSig argument 0
• Mode: Signature

arg_1

• Opcode: 0x2e
• Stack: ... → ..., []byte
• LogicSig argument 1
• Mode: Signature

arg_2

• Opcode: 0x2f
• Stack: ... → ..., []byte
• LogicSig argument 2
• Mode: Signature

arg_3

• Opcode: 0x30
• Stack: ... → ..., []byte
• LogicSig argument 3
• Mode: Signature

txn f

• Opcode: 0x31 {uint8 transaction field index}
• Stack: ... → ..., any
• field F of current transaction

txn Fields (see transaction reference):

Index	Name	Type	In	Notes
0	Sender	[]byte		32 byte address
1	Fee	uint64		microalgos
2	FirstValid	uint64		round number
3	FirstValidTime	uint64	v7	UNIX timestamp of block before txn.FirstValid. Fails if negative
4	LastValid	uint64		round number
5	Note	[]byte		Any data up to 1024 bytes
6	Lease	[]byte		32 byte lease value
7	Receiver	[]byte		32 byte address
8	Amount	uint64		microalgos
9	CloseRemainderTo	[]byte		32 byte address
10	VotePK	[]byte		32 byte address
11	SelectionPK	[]byte		32 byte address
12	VoteFirst	uint64		The first round that the participation key is valid.
13	VoteLast	uint64		The last round that the participation key is valid.
14	VoteKeyDilution	uint64		Dilution for the 2-level participation key
15	Type	[]byte		Transaction type as bytes
16	TypeEnum	uint64		Transaction type as integer
17	XferAsset	uint64		Asset ID
18	AssetAmount	uint64		value in Asset's units
19	AssetSender	[]byte		32 byte address. Source of assets if Sender is the Asset's Clawback address.
20	AssetReceiver	[]byte		32 byte address
21	AssetCloseTo	[]byte		32 byte address
22	GroupIndex	uint64		Position of this transaction within an atomic transaction group. A stand-alone transaction is implicitly element 0 in a group of 1
23	TxID	[]byte		The computed ID for this transaction. 32 bytes.
24	ApplicationID	uint64	v2	ApplicationID from ApplicationCall transaction
25	OnCompletion	uint64	v2	ApplicationCall transaction on completion action
27	NumAppArgs	uint64	v2	Number of ApplicationArgs
29	NumAccounts	uint64	v2	Number of Accounts
30	ApprovalProgram	[]byte	v2	Approval program
31	ClearStateProgram	[]byte	v2	Clear state program
32	RekeyTo	[]byte	v2	32 byte Sender's new AuthAddr
33	ConfigAsset	uint64	v2	Asset ID in asset config transaction
34	ConfigAssetTotal	uint64	v2	Total number of units of this asset created
35	ConfigAssetDecimals	uint64	v2	Number of digits to display after the decimal place when displaying the asset
36	ConfigAssetDefaultFrozen	uint64	v2	Whether the asset's slots are frozen by default or not, 0 or 1
37	ConfigAssetUnitName	[]byte	v2	Unit name of the asset
38	ConfigAssetName	[]byte	v2	The asset name
39	ConfigAssetURL	[]byte	v2	URL
40	ConfigAssetMetadataHash	[]byte	v2	32 byte commitment to unspecified asset metadata
41	ConfigAssetManager	[]byte	v2	32 byte address
42	ConfigAssetReserve	[]byte	v2	32 byte address
43	ConfigAssetFreeze	[]byte	v2	32 byte address
44	ConfigAssetClawback	[]byte	v2	32 byte address
45	FreezeAsset	uint64	v2	Asset ID being frozen or un-frozen
46	FreezeAssetAccount	[]byte	v2	32 byte address of the account whose asset slot is being frozen or un-frozen
47	FreezeAssetFrozen	uint64	v2	The new frozen value, 0 or 1
49	NumAssets	uint64	v3	Number of Assets
51	NumApplications	uint64	v3	Number of Applications
52	GlobalNumUint	uint64	v3	Number of global state integers in ApplicationCall
53	GlobalNumByteSlice	uint64	v3	Number of global state byteslices in ApplicationCall
54	LocalNumUint	uint64	v3	Number of local state integers in ApplicationCall
55	LocalNumByteSlice	uint64	v3	Number of local state byteslices in ApplicationCall
56	ExtraProgramPages	uint64	v4	Number of additional pages for each of the application's approval and clear state programs. An ExtraProgramPages of 1 means 2048 more total bytes, or 1024 for each program.
57	Nonparticipation	uint64	v5	Marks an account nonparticipating for rewards
59	NumLogs	uint64	v5	Number of Logs (only with itxn in v5). Application mode only
60	CreatedAssetID	uint64	v5	Asset ID allocated by the creation of an ASA (only with itxn in v5). Application mode only
61	CreatedApplicationID	uint64	v5	ApplicationID allocated by the creation of an application (only with itxn in v5). Application mode only
62	LastLog	[]byte	v6	The last message emitted. Empty bytes if none were emitted. Application mode only
63	StateProofPK	[]byte	v6	64 byte state proof public key
65	NumApprovalProgramPages	uint64	v7	Number of Approval Program pages
67	NumClearStateProgramPages	uint64	v7	Number of ClearState Program pages

global f

• Opcode: 0x32 {uint8 global field index}
• Stack: ... → ..., any
• global field F

global Fields:

Index	Name	Type	In	Notes
0	MinTxnFee	uint64		microalgos
1	MinBalance	uint64		microalgos
2	MaxTxnLife	uint64		rounds
3	ZeroAddress	[]byte		32 byte address of all zero bytes
4	GroupSize	uint64		Number of transactions in this atomic transaction group. At least 1
5	LogicSigVersion	uint64	v2	Maximum supported version
6	Round	uint64	v2	Current round number. Application mode only.
7	LatestTimestamp	uint64	v2	Last confirmed block UNIX timestamp. Fails if negative. Application mode only.
8	CurrentApplicationID	uint64	v2	ID of current application executing. Application mode only.
9	CreatorAddress	[]byte	v3	Address of the creator of the current application. Application mode only.
10	CurrentApplicationAddress	[]byte	v5	Address that the current application controls. Application mode only.
11	GroupID	[]byte	v5	ID of the transaction group. 32 zero bytes if the transaction is not part of a group.
12	OpcodeBudget	uint64	v6	The remaining cost that can be spent by opcodes in this program.
13	CallerApplicationID	uint64	v6	The application ID of the application that called this application. 0 if this application is at the top-level. Application mode only.
14	CallerApplicationAddress	[]byte	v6	The application address of the application that called this application. ZeroAddress if this application is at the top-level. Application mode only.

gtxn t f

• Opcode: 0x33 {uint8 transaction group index} {uint8 transaction field index}
• Stack: ... → ..., any
• field F of the Tth transaction in the current group

for notes on transaction fields available, see txn. If this transaction is i in the group, gtxn i field is equivalent to txn field.

load i

• Opcode: 0x34 {uint8 position in scratch space to load from}
• Stack: ... → ..., any
• Ith scratch space value. All scratch spaces are 0 at program start.

store i

• Opcode: 0x35 {uint8 position in scratch space to store to}
• Stack: ..., A → ...
• store A to the Ith scratch space

txna f i

• Opcode: 0x36 {uint8 transaction field index} {uint8 transaction field array index}
• Stack: ... → ..., any
• Ith value of the array field F of the current transaction
  txna can be called using txn with 2 immediates.
• Availability: v2

txna Fields (see transaction reference):

Index	Name	Type	In	Notes
26	ApplicationArgs	[]byte	v2	Arguments passed to the application in the ApplicationCall transaction
28	Accounts	[]byte	v2	Accounts listed in the ApplicationCall transaction
48	Assets	uint64	v3	Foreign Assets listed in the ApplicationCall transaction
50	Applications	uint64	v3	Foreign Apps listed in the ApplicationCall transaction
58	Logs	[]byte	v5	Log messages emitted by an application call (only with itxn in v5). Application mode only
64	ApprovalProgramPages	[]byte	v7	Approval Program as an array of pages
66	ClearStateProgramPages	[]byte	v7	ClearState Program as an array of pages

gtxna t f i

• Opcode: 0x37 {uint8 transaction group index} {uint8 transaction field index} {uint8 transaction field array index}
• Stack: ... → ..., any
• Ith value of the array field F from the Tth transaction in the current group
  gtxna can be called using gtxn with 3 immediates.
• Availability: v2

gtxns f

• Opcode: 0x38 {uint8 transaction field index}
• Stack: ..., A: uint64 → ..., any
• field F of the Ath transaction in the current group
• Availability: v3

for notes on transaction fields available, see txn. If top of stack is i, gtxns field is equivalent to gtxn _i_ field. gtxns exists so that i can be calculated, often based on the index of the current transaction.

gtxnsa f i

• Opcode: 0x39 {uint8 transaction field index} {uint8 transaction field array index}
• Stack: ..., A: uint64 → ..., any
• Ith value of the array field F from the Ath transaction in the current group
  gtxnsa can be called using gtxns with 2 immediates.
• Availability: v3

gload t i

• Opcode: 0x3a {uint8 transaction group index} {uint8 position in scratch space to load from}
• Stack: ... → ..., any
• Ith scratch space value of the Tth transaction in the current group
• Availability: v4
• Mode: Application

gload fails unless the requested transaction is an ApplicationCall and T < GroupIndex.

gloads i

• Opcode: 0x3b {uint8 position in scratch space to load from}
• Stack: ..., A: uint64 → ..., any
• Ith scratch space value of the Ath transaction in the current group
• Availability: v4
• Mode: Application

gloads fails unless the requested transaction is an ApplicationCall and A < GroupIndex.

gaid t

• Opcode: 0x3c {uint8 transaction group index}
• Stack: ... → ..., uint64
• ID of the asset or application created in the Tth transaction of the current group
• Availability: v4
• Mode: Application

gaid fails unless the requested transaction created an asset or application and T < GroupIndex.

gaids

• Opcode: 0x3d
• Stack: ..., A: uint64 → ..., uint64
• ID of the asset or application created in the Ath transaction of the current group
• Availability: v4
• Mode: Application

gaids fails unless the requested transaction created an asset or application and A < GroupIndex.

loads

• Opcode: 0x3e
• Stack: ..., A: uint64 → ..., any
• Ath scratch space value. All scratch spaces are 0 at program start.
• Availability: v5

stores

• Opcode: 0x3f
• Stack: ..., A: uint64, B → ...
• store B to the Ath scratch space
• Availability: v5

bnz target

• Opcode: 0x40 {int16 branch offset, big-endian}
• Stack: ..., A: uint64 → ...
• branch to TARGET if value A is not zero

The bnz instruction opcode 0x40 is followed by two immediate data bytes which are a high byte first and low byte second which together form a 16 bit offset which the instruction may branch to. For a bnz instruction at pc, if the last element of the stack is not zero then branch to instruction at pc + 3 + N, else proceed to next instruction at pc + 3. Branch targets must be aligned instructions. (e.g. Branching to the second byte of a 2 byte op will be rejected.) Starting at v4, the offset is treated as a signed 16 bit integer allowing for backward branches and looping. In prior version (v1 to v3), branch offsets are limited to forward branches only, 0-0x7fff.

At v2 it became allowed to branch to the end of the program exactly after the last instruction: bnz to byte N (with 0-indexing) was illegal for a TEAL program with N bytes before v2, and is legal after it. This change eliminates the need for a last instruction of no-op as a branch target at the end. (Branching beyond the end--in other words, to a byte larger than N--is still illegal and will cause the program to fail.)

bz target

• Opcode: 0x41 {int16 branch offset, big-endian}
• Stack: ..., A: uint64 → ...
• branch to TARGET if value A is zero
• Availability: v2

See bnz for details on how branches work. bz inverts the behavior of bnz.

b target

• Opcode: 0x42 {int16 branch offset, big-endian}
• Stack: ... → ...
• branch unconditionally to TARGET
• Availability: v2

See bnz for details on how branches work. b always jumps to the offset.

return

• Opcode: 0x43
• Stack: ..., A: uint64 → exits
• use A as success value; end
• Availability: v2

assert

• Opcode: 0x44
• Stack: ..., A: uint64 → ...
• immediately fail unless A is a non-zero number
• Availability: v3

pop

• Opcode: 0x48
• Stack: ..., A → ...
• discard A

dup

• Opcode: 0x49
• Stack: ..., A → ..., A, A
• duplicate A

dup2

• Opcode: 0x4a
• Stack: ..., A, B → ..., A, B, A, B
• duplicate A and B
• Availability: v2

dig n

• Opcode: 0x4b {uint8 depth}
• Stack: ..., A, [N items] → ..., A, [N items], A
• Nth value from the top of the stack. dig 0 is equivalent to dup
• Availability: v3

swap

• Opcode: 0x4c
• Stack: ..., A, B → ..., B, A
• swaps A and B on stack
• Availability: v3

select

• Opcode: 0x4d
• Stack: ..., A, B, C: uint64 → ..., A or B
• selects one of two values based on top-of-stack: B if C != 0, else A
• Availability: v3

cover n

• Opcode: 0x4e {uint8 depth}
• Stack: ..., [N items], A → ..., A, [N items]
• remove top of stack, and place it deeper in the stack such that N elements are above it. Fails if stack depth <= N.
• Availability: v5

uncover n

• Opcode: 0x4f {uint8 depth}
• Stack: ..., A, [N items] → ..., [N items], A
• remove the value at depth N in the stack and shift above items down so the Nth deep value is on top of the stack. Fails if stack depth <= N.
• Availability: v5

concat

• Opcode: 0x50
• Stack: ..., A: []byte, B: []byte → ..., []byte
• join A and B
• Availability: v2

concat fails if the result would be greater than 4096 bytes.

substring s e

• Opcode: 0x51 {uint8 start position} {uint8 end position}
• Stack: ..., A: []byte → ..., []byte
• A range of bytes from A starting at S up to but not including E. If E < S, or either is larger than the array length, the program fails
• Availability: v2

substring3

• Opcode: 0x52
• Stack: ..., A: []byte, B: uint64, C: uint64 → ..., []byte
• A range of bytes from A starting at B up to but not including C. If C < B, or either is larger than the array length, the program fails
• Availability: v2

getbit

• Opcode: 0x53
• Stack: ..., A, B: uint64 → ..., uint64
• Bth bit of (byte-array or integer) A. If B is greater than or equal to the bit length of the value (8*byte length), the program fails
• Availability: v3

see explanation of bit ordering in setbit

setbit

• Opcode: 0x54
• Stack: ..., A, B: uint64, C: uint64 → ..., any
• Copy of (byte-array or integer) A, with the Bth bit set to (0 or 1) C. If B is greater than or equal to the bit length of the value (8*byte length), the program fails
• Availability: v3

When A is a uint64, index 0 is the least significant bit. Setting bit 3 to 1 on the integer 0 yields 8, or 2^3. When A is a byte array, index 0 is the leftmost bit of the leftmost byte. Setting bits 0 through 11 to 1 in a 4-byte-array of 0s yields the byte array 0xfff00000. Setting bit 3 to 1 on the 1-byte-array 0x00 yields the byte array 0x10.

getbyte

• Opcode: 0x55
• Stack: ..., A: []byte, B: uint64 → ..., uint64
• Bth byte of A, as an integer. If B is greater than or equal to the array length, the program fails
• Availability: v3

setbyte

• Opcode: 0x56
• Stack: ..., A: []byte, B: uint64, C: uint64 → ..., []byte
• Copy of A with the Bth byte set to small integer (between 0..255) C. If B is greater than or equal to the array length, the program fails
• Availability: v3

extract s l

• Opcode: 0x57 {uint8 start position} {uint8 length}
• Stack: ..., A: []byte → ..., []byte
• A range of bytes from A starting at S up to but not including S+L. If L is 0, then extract to the end of the string. If S or S+L is larger than the array length, the program fails
• Availability: v5

extract3

• Opcode: 0x58
• Stack: ..., A: []byte, B: uint64, C: uint64 → ..., []byte
• A range of bytes from A starting at B up to but not including B+C. If B+C is larger than the array length, the program fails
  extract3 can be called using extract with no immediates.
• Availability: v5

extract_uint16

• Opcode: 0x59
• Stack: ..., A: []byte, B: uint64 → ..., uint64
• A uint16 formed from a range of big-endian bytes from A starting at B up to but not including B+2. If B+2 is larger than the array length, the program fails
• Availability: v5

extract_uint32

• Opcode: 0x5a
• Stack: ..., A: []byte, B: uint64 → ..., uint64
• A uint32 formed from a range of big-endian bytes from A starting at B up to but not including B+4. If B+4 is larger than the array length, the program fails
• Availability: v5

extract_uint64

• Opcode: 0x5b
• Stack: ..., A: []byte, B: uint64 → ..., uint64
• A uint64 formed from a range of big-endian bytes from A starting at B up to but not including B+8. If B+8 is larger than the array length, the program fails
• Availability: v5

replace2 s

• Opcode: 0x5c {uint8 start position}
• Stack: ..., A: []byte, B: []byte → ..., []byte
• Copy of A with the bytes starting at S replaced by the bytes of B. Fails if S+len(B) exceeds len(A)
  replace2 can be called using replace with 1 immediate.
• Availability: v7

replace3

• Opcode: 0x5d
• Stack: ..., A: []byte, B: uint64, C: []byte → ..., []byte
• Copy of A with the bytes starting at B replaced by the bytes of C. Fails if B+len(C) exceeds len(A)
  replace3 can be called using replace with no immediates.
• Availability: v7

base64_decode e

• Opcode: 0x5e {uint8 encoding index}
• Stack: ..., A: []byte → ..., []byte
• decode A which was base64-encoded using encoding E. Fail if A is not base64 encoded with encoding E
• Cost: 1 + 1 per 16 bytes of A
• Availability: v7

base64 Encodings:

Index	Name	Notes
0	URLEncoding
1	StdEncoding

Warning: Usage should be restricted to very rare use cases. In almost all cases, smart contracts should directly handle non-encoded byte-strings. This opcode should only be used in cases where base64 is the only available option, e.g. interoperability with a third-party that only signs base64 strings.

Decodes A using the base64 encoding E. Specify the encoding with an immediate arg either as URL and Filename Safe (URLEncoding) or Standard (StdEncoding). See RFC 4648 sections 4 and 5. It is assumed that the encoding ends with the exact number of = padding characters as required by the RFC. When padding occurs, any unused pad bits in the encoding must be set to zero or the decoding will fail. The special cases of \n and \r are allowed but completely ignored. An error will result when attempting to decode a string with a character that is not in the encoding alphabet or not one of =, \r, or \n.

json_ref r

• Opcode: 0x5f {string return type}
• Stack: ..., A: []byte, B: []byte → ..., any
• key B's value, of type R, from a valid utf-8 encoded json object A
• Cost: 25 + 2 per 7 bytes of A
• Availability: v7

json_ref Types:

Index	Name	Type	Notes
0	JSONString	[]byte
1	JSONUint64	uint64
2	JSONObject	[]byte

Warning: Usage should be restricted to very rare use cases, as JSON decoding is expensive and quite limited. In addition, JSON objects are large and not optimized for size.

Almost all smart contracts should use simpler and smaller methods (such as the ABI. This opcode should only be used in cases where JSON is only available option, e.g. when a third-party only signs JSON.

balance

• Opcode: 0x60
• Stack: ..., A → ..., uint64
• get balance for account A, in microalgos. The balance is observed after the effects of previous transactions in the group, and after the fee for the current transaction is deducted.
• Availability: v2
• Mode: Application

params: Txn.Accounts offset (or, since v4, an available account address), available application id (or, since v4, a Txn.ForeignApps offset). Return: value.

app_opted_in

• Opcode: 0x61
• Stack: ..., A, B: uint64 → ..., uint64
• 1 if account A is opted in to application B, else 0
• Availability: v2
• Mode: Application

params: Txn.Accounts offset (or, since v4, an available account address), available application id (or, since v4, a Txn.ForeignApps offset). Return: 1 if opted in and 0 otherwise.

app_local_get

• Opcode: 0x62
• Stack: ..., A, B: []byte → ..., any
• local state of the key B in the current application in account A
• Availability: v2
• Mode: Application

params: Txn.Accounts offset (or, since v4, an available account address), state key. Return: value. The value is zero (of type uint64) if the key does not exist.

app_local_get_ex

• Opcode: 0x63
• Stack: ..., A, B: uint64, C: []byte → ..., X: any, Y: uint64
• X is the local state of application B, key C in account A. Y is 1 if key existed, else 0
• Availability: v2
• Mode: Application

params: Txn.Accounts offset (or, since v4, an available account address), available application id (or, since v4, a Txn.ForeignApps offset), state key. Return: did_exist flag (top of the stack, 1 if the application and key existed and 0 otherwise), value. The value is zero (of type uint64) if the key does not exist.

app_global_get

• Opcode: 0x64
• Stack: ..., A: []byte → ..., any
• global state of the key A in the current application
• Availability: v2
• Mode: Application

params: state key. Return: value. The value is zero (of type uint64) if the key does not exist.

app_global_get_ex

• Opcode: 0x65
• Stack: ..., A: uint64, B: []byte → ..., X: any, Y: uint64
• X is the global state of application A, key B. Y is 1 if key existed, else 0
• Availability: v2
• Mode: Application

params: Txn.ForeignApps offset (or, since v4, an available application id), state key. Return: did_exist flag (top of the stack, 1 if the application and key existed and 0 otherwise), value. The value is zero (of type uint64) if the key does not exist.

app_local_put

• Opcode: 0x66
• Stack: ..., A, B: []byte, C → ...
• write C to key B in account A's local state of the current application
• Availability: v2
• Mode: Application

params: Txn.Accounts offset (or, since v4, an available account address), state key, value.

app_global_put

• Opcode: 0x67
• Stack: ..., A: []byte, B → ...
• write B to key A in the global state of the current application
• Availability: v2
• Mode: Application

app_local_del

• Opcode: 0x68
• Stack: ..., A, B: []byte → ...
• delete key B from account A's local state of the current application
• Availability: v2
• Mode: Application

params: Txn.Accounts offset (or, since v4, an available account address), state key.

Deleting a key which is already absent has no effect on the application local state. (In particular, it does not cause the program to fail.)

app_global_del

• Opcode: 0x69
• Stack: ..., A: []byte → ...
• delete key A from the global state of the current application
• Availability: v2
• Mode: Application

params: state key.

Deleting a key which is already absent has no effect on the application global state. (In particular, it does not cause the program to fail.)

asset_holding_get f

• Opcode: 0x70 {uint8 asset holding field index}
• Stack: ..., A, B: uint64 → ..., X: any, Y: uint64
• X is field F from account A's holding of asset B. Y is 1 if A is opted into B, else 0
• Availability: v2
• Mode: Application

asset_holding Fields:

Index	Name	Type	Notes
0	AssetBalance	uint64	Amount of the asset unit held by this account
1	AssetFrozen	uint64	Is the asset frozen or not

params: Txn.Accounts offset (or, since v4, an available address), asset id (or, since v4, a Txn.ForeignAssets offset). Return: did_exist flag (1 if the asset existed and 0 otherwise), value.

asset_params_get f

• Opcode: 0x71 {uint8 asset params field index}
• Stack: ..., A: uint64 → ..., X: any, Y: uint64
• X is field F from asset A. Y is 1 if A exists, else 0
• Availability: v2
• Mode: Application

asset_params Fields:

Index	Name	Type	In	Notes
0	AssetTotal	uint64		Total number of units of this asset
1	AssetDecimals	uint64		See AssetParams.Decimals
2	AssetDefaultFrozen	uint64		Frozen by default or not
3	AssetUnitName	[]byte		Asset unit name
4	AssetName	[]byte		Asset name
5	AssetURL	[]byte		URL with additional info about the asset
6	AssetMetadataHash	[]byte		Arbitrary commitment
7	AssetManager	[]byte		Manager address
8	AssetReserve	[]byte		Reserve address
9	AssetFreeze	[]byte		Freeze address
10	AssetClawback	[]byte		Clawback address
11	AssetCreator	[]byte	v5	Creator address

params: Txn.ForeignAssets offset (or, since v4, an available asset id. Return: did_exist flag (1 if the asset existed and 0 otherwise), value.

app_params_get f

• Opcode: 0x72 {uint8 app params field index}
• Stack: ..., A: uint64 → ..., X: any, Y: uint64
• X is field F from app A. Y is 1 if A exists, else 0
• Availability: v5
• Mode: Application

app_params Fields:

Index	Name	Type	Notes
0	AppApprovalProgram	[]byte	Bytecode of Approval Program
1	AppClearStateProgram	[]byte	Bytecode of Clear State Program
2	AppGlobalNumUint	uint64	Number of uint64 values allowed in Global State
3	AppGlobalNumByteSlice	uint64	Number of byte array values allowed in Global State
4	AppLocalNumUint	uint64	Number of uint64 values allowed in Local State
5	AppLocalNumByteSlice	uint64	Number of byte array values allowed in Local State
6	AppExtraProgramPages	uint64	Number of Extra Program Pages of code space
7	AppCreator	[]byte	Creator address
8	AppAddress	[]byte	Address for which this application has authority

params: Txn.ForeignApps offset or an available app id. Return: did_exist flag (1 if the application existed and 0 otherwise), value.

acct_params_get f

• Opcode: 0x73 {uint8 account params field index}
• Stack: ..., A → ..., X: any, Y: uint64
• X is field F from account A. Y is 1 if A owns positive algos, else 0
• Availability: v6
• Mode: Application

acct_params Fields:

Index	Name	Type	Notes
0	AcctBalance	uint64	Account balance in microalgos
1	AcctMinBalance	uint64	Minimum required blance for account, in microalgos
2	AcctAuthAddr	[]byte	Address the account is rekeyed to.

min_balance

• Opcode: 0x78
• Stack: ..., A → ..., uint64
• get minimum required balance for account A, in microalgos. Required balance is affected by ASA and App usage. When creating or opting into an app, the minimum balance grows before the app code runs, therefore the increase is visible there. When deleting or closing out, the minimum balance decreases after the app executes.
• Availability: v3
• Mode: Application

params: Txn.Accounts offset (or, since v4, an available account address), available application id (or, since v4, a Txn.ForeignApps offset). Return: value.

pushbytes bytes

• Opcode: 0x80 {varuint length} {bytes}
• Stack: ... → ..., []byte
• immediate BYTES
• Availability: v3

pushbytes args are not added to the bytecblock during assembly processes

pushint uint

• Opcode: 0x81 {varuint int}
• Stack: ... → ..., uint64
• immediate UINT
• Availability: v3

pushint args are not added to the intcblock during assembly processes

ed25519verify_bare

• Opcode: 0x84
• Stack: ..., A: []byte, B: []byte, C: []byte → ..., uint64
• for (data A, signature B, pubkey C) verify the signature of the data against the pubkey => {0 or 1}
• Cost: 1900
• Availability: v7

callsub target

• Opcode: 0x88 {int16 branch offset, big-endian}
• Stack: ... → ...
• branch unconditionally to TARGET, saving the next instruction on the call stack
• Availability: v4

The call stack is separate from the data stack. Only callsub and retsub manipulate it.

retsub

• Opcode: 0x89
• Stack: ... → ...
• pop the top instruction from the call stack and branch to it
• Availability: v4

The call stack is separate from the data stack. Only callsub and retsub manipulate it.

shl

• Opcode: 0x90
• Stack: ..., A: uint64, B: uint64 → ..., uint64
• A times 2^B, modulo 2^64
• Availability: v4

shr

• Opcode: 0x91
• Stack: ..., A: uint64, B: uint64 → ..., uint64
• A divided by 2^B
• Availability: v4

sqrt

• Opcode: 0x92
• Stack: ..., A: uint64 → ..., uint64
• The largest integer I such that I^2 <= A
• Cost: 4
• Availability: v4

bitlen

• Opcode: 0x93
• Stack: ..., A → ..., uint64
• The highest set bit in A. If A is a byte-array, it is interpreted as a big-endian unsigned integer. bitlen of 0 is 0, bitlen of 8 is 4
• Availability: v4

bitlen interprets arrays as big-endian integers, unlike setbit/getbit

exp

• Opcode: 0x94
• Stack: ..., A: uint64, B: uint64 → ..., uint64
• A raised to the Bth power. Fail if A == B == 0 and on overflow
• Availability: v4

expw

• Opcode: 0x95
• Stack: ..., A: uint64, B: uint64 → ..., X: uint64, Y: uint64
• A raised to the Bth power as a 128-bit result in two uint64s. X is the high 64 bits, Y is the low. Fail if A == B == 0 or if the results exceeds 2^128-1
• Cost: 10
• Availability: v4

bsqrt

• Opcode: 0x96
• Stack: ..., A: []byte → ..., []byte
• The largest integer I such that I^2 <= A. A and I are interpreted as big-endian unsigned integers
• Cost: 40
• Availability: v6

divw

• Opcode: 0x97
• Stack: ..., A: uint64, B: uint64, C: uint64 → ..., uint64
• A,B / C. Fail if C == 0 or if result overflows.
• Availability: v6

The notation A,B indicates that A and B are interpreted as a uint128 value, with A as the high uint64 and B the low.

sha3_256

• Opcode: 0x98
• Stack: ..., A: []byte → ..., []byte
• SHA3_256 hash of value A, yields [32]byte
• Cost: 130
• Availability: v7

b+

• Opcode: 0xa0
• Stack: ..., A: []byte, B: []byte → ..., []byte
• A plus B. A and B are interpreted as big-endian unsigned integers
• Cost: 10
• Availability: v4

b-

• Opcode: 0xa1
• Stack: ..., A: []byte, B: []byte → ..., []byte
• A minus B. A and B are interpreted as big-endian unsigned integers. Fail on underflow.
• Cost: 10
• Availability: v4

b/

• Opcode: 0xa2
• Stack: ..., A: []byte, B: []byte → ..., []byte
• A divided by B (truncated division). A and B are interpreted as big-endian unsigned integers. Fail if B is zero.
• Cost: 20
• Availability: v4

b*

• Opcode: 0xa3
• Stack: ..., A: []byte, B: []byte → ..., []byte
• A times B. A and B are interpreted as big-endian unsigned integers.
• Cost: 20
• Availability: v4

b<

• Opcode: 0xa4
• Stack: ..., A: []byte, B: []byte → ..., uint64
• 1 if A is less than B, else 0. A and B are interpreted as big-endian unsigned integers
• Availability: v4

b>

• Opcode: 0xa5
• Stack: ..., A: []byte, B: []byte → ..., uint64
• 1 if A is greater than B, else 0. A and B are interpreted as big-endian unsigned integers
• Availability: v4

b<=

• Opcode: 0xa6
• Stack: ..., A: []byte, B: []byte → ..., uint64
• 1 if A is less than or equal to B, else 0. A and B are interpreted as big-endian unsigned integers
• Availability: v4

b>=

• Opcode: 0xa7
• Stack: ..., A: []byte, B: []byte → ..., uint64
• 1 if A is greater than or equal to B, else 0. A and B are interpreted as big-endian unsigned integers
• Availability: v4

b==

• Opcode: 0xa8
• Stack: ..., A: []byte, B: []byte → ..., uint64
• 1 if A is equal to B, else 0. A and B are interpreted as big-endian unsigned integers
• Availability: v4

b!=

• Opcode: 0xa9
• Stack: ..., A: []byte, B: []byte → ..., uint64
• 0 if A is equal to B, else 1. A and B are interpreted as big-endian unsigned integers
• Availability: v4

b%

• Opcode: 0xaa
• Stack: ..., A: []byte, B: []byte → ..., []byte
• A modulo B. A and B are interpreted as big-endian unsigned integers. Fail if B is zero.
• Cost: 20
• Availability: v4

b|

• Opcode: 0xab
• Stack: ..., A: []byte, B: []byte → ..., []byte
• A bitwise-or B. A and B are zero-left extended to the greater of their lengths
• Cost: 6
• Availability: v4

b&

• Opcode: 0xac
• Stack: ..., A: []byte, B: []byte → ..., []byte
• A bitwise-and B. A and B are zero-left extended to the greater of their lengths
• Cost: 6
• Availability: v4

b^

• Opcode: 0xad
• Stack: ..., A: []byte, B: []byte → ..., []byte
• A bitwise-xor B. A and B are zero-left extended to the greater of their lengths
• Cost: 6
• Availability: v4

b~

• Opcode: 0xae
• Stack: ..., A: []byte → ..., []byte
• A with all bits inverted
• Cost: 4
• Availability: v4

bzero

• Opcode: 0xaf
• Stack: ..., A: uint64 → ..., []byte
• zero filled byte-array of length A
• Availability: v4

log

• Opcode: 0xb0
• Stack: ..., A: []byte → ...
• write A to log state of the current application
• Availability: v5
• Mode: Application

log fails if called more than MaxLogCalls times in a program, or if the sum of logged bytes exceeds 1024 bytes.

itxn_begin

• Opcode: 0xb1
• Stack: ... → ...
• begin preparation of a new inner transaction in a new transaction group
• Availability: v5
• Mode: Application

itxn_begin initializes Sender to the application address; Fee to the minimum allowable, taking into account MinTxnFee and credit from overpaying in earlier transactions; FirstValid/LastValid to the values in the invoking transaction, and all other fields to zero or empty values.

itxn_field f

• Opcode: 0xb2 {uint8 transaction field index}
• Stack: ..., A → ...
• set field F of the current inner transaction to A
• Availability: v5
• Mode: Application

itxn_field fails if A is of the wrong type for F, including a byte array of the wrong size for use as an address when F is an address field. itxn_field also fails if A is an account, asset, or app that is not available, or an attempt is made extend an array field beyond the limit imposed by consensus parameters. (Addresses set into asset params of acfg transactions need not be available.)

itxn_submit

• Opcode: 0xb3
• Stack: ... → ...
• execute the current inner transaction group. Fail if executing this group would exceed the inner transaction limit, or if any transaction in the group fails.
• Availability: v5
• Mode: Application

itxn_submit resets the current transaction so that it can not be resubmitted. A new itxn_begin is required to prepare another inner transaction.

itxn f

• Opcode: 0xb4 {uint8 transaction field index}
• Stack: ... → ..., any
• field F of the last inner transaction
• Availability: v5
• Mode: Application

itxna f i

• Opcode: 0xb5 {uint8 transaction field index} {uint8 transaction field array index}
• Stack: ... → ..., any
• Ith value of the array field F of the last inner transaction
• Availability: v5
• Mode: Application

itxn_next

• Opcode: 0xb6
• Stack: ... → ...
• begin preparation of a new inner transaction in the same transaction group
• Availability: v6
• Mode: Application

itxn_next initializes the transaction exactly as itxn_begin does

gitxn t f

• Opcode: 0xb7 {uint8 transaction group index} {uint8 transaction field index}
• Stack: ... → ..., any
• field F of the Tth transaction in the last inner group submitted
• Availability: v6
• Mode: Application

gitxna t f i

• Opcode: 0xb8 {uint8 transaction group index} {uint8 transaction field index} {uint8 transaction field array index}
• Stack: ... → ..., any
• Ith value of the array field F from the Tth transaction in the last inner group submitted
• Availability: v6
• Mode: Application

txnas f

• Opcode: 0xc0 {uint8 transaction field index}
• Stack: ..., A: uint64 → ..., any
• Ath value of the array field F of the current transaction
• Availability: v5

gtxnas t f

• Opcode: 0xc1 {uint8 transaction group index} {uint8 transaction field index}
• Stack: ..., A: uint64 → ..., any
• Ath value of the array field F from the Tth transaction in the current group
• Availability: v5

gtxnsas f

• Opcode: 0xc2 {uint8 transaction field index}
• Stack: ..., A: uint64, B: uint64 → ..., any
• Bth value of the array field F from the Ath transaction in the current group
• Availability: v5

args

• Opcode: 0xc3
• Stack: ..., A: uint64 → ..., []byte
• Ath LogicSig argument
• Availability: v5
• Mode: Signature

gloadss

• Opcode: 0xc4
• Stack: ..., A: uint64, B: uint64 → ..., any
• Bth scratch space value of the Ath transaction in the current group
• Availability: v6
• Mode: Application

itxnas f

• Opcode: 0xc5 {uint8 transaction field index}
• Stack: ..., A: uint64 → ..., any
• Ath value of the array field F of the last inner transaction
• Availability: v6
• Mode: Application

gitxnas t f

• Opcode: 0xc6 {uint8 transaction group index} {uint8 transaction field index}
• Stack: ..., A: uint64 → ..., any
• Ath value of the array field F from the Tth transaction in the last inner group submitted
• Availability: v6
• Mode: Application

vrf_verify s

• Opcode: 0xd0 {uint8 parameters index}
• Stack: ..., A: []byte, B: []byte, C: []byte → ..., X: []byte, Y: uint64
• Verify the proof B of message A against pubkey C. Returns vrf output and verification flag.
• Cost: 5700
• Availability: v7

vrf_verify Standards:

Index	Name	Notes
0	VrfAlgorand

VrfAlgorand is the VRF used in Algorand. It is ECVRF-ED25519-SHA512-Elligator2, specified in the IETF internet draft draft-irtf-cfrg-vrf-03.

block f

• Opcode: 0xd1 {uint8 block field}
• Stack: ..., A: uint64 → ..., any
• field F of block A. Fail unless A falls between txn.LastValid-1002 and the current round (exclusive)
• Availability: v7

block Fields:

Index	Name	Type	Notes
0	BlkSeed	[]byte
1	BlkTimestamp	uint64