opcodetype

Name

Description

OP_0

Pushes an empty byte array (numeric zero / false) onto the stack.

OP_FALSE

Alias for OP_0.

OP_PUSHDATA1

Pushes the next byte's count of bytes onto the stack.

OP_PUSHDATA2

Pushes the next two bytes' count of bytes onto the stack.

OP_PUSHDATA4

Pushes the next four bytes' count of bytes onto the stack.

OP_1NEGATE

Pushes the number ‐1 onto the stack.

OP_RESERVED

Reserved opcode; makes the transaction invalid if executed.

OP_1

Pushes the number 1 onto the stack.

OP_TRUE

Alias for OP_1.

OP_2

Pushes the number 2 onto the stack.

OP_3

Pushes the number 3 onto the stack.

OP_4

Pushes the number 4 onto the stack.

OP_5

Pushes the number 5 onto the stack.

OP_6

Pushes the number 6 onto the stack.

OP_7

Pushes the number 7 onto the stack.

OP_8

Pushes the number 8 onto the stack.

OP_9

Pushes the number 9 onto the stack.

OP_10

Pushes the number 10 onto the stack.

OP_11

Pushes the number 11 onto the stack.

OP_12

Pushes the number 12 onto the stack.

OP_13

Pushes the number 13 onto the stack.

OP_14

Pushes the number 14 onto the stack.

OP_15

Pushes the number 15 onto the stack.

OP_16

Pushes the number 16 onto the stack.

OP_NOP

Does nothing.

OP_VER

Reserved opcode; makes the transaction invalid if executed.

OP_IF

Executes the following block if the top stack value is true.

OP_NOTIF

Executes the following block if the top stack value is false.

OP_VERIF

Reserved opcode; makes the transaction invalid even when unexecuted.

OP_VERNOTIF

Reserved opcode; makes the transaction invalid even when unexecuted.

OP_ELSE

Executes the following block if the preceding OP_IF/OP_NOTIF block was not.

OP_ENDIF

Ends an OP_IF/OP_NOTIF/OP_ELSE block.

OP_VERIFY

Marks the transaction invalid if the top stack value is not true.

OP_RETURN

Marks the transaction invalid and the output provably unspendable.

OP_TOALTSTACK

Moves the top item from the main stack to the alt stack.

OP_FROMALTSTACK

Moves the top item from the alt stack to the main stack.

OP_2DROP

Removes the top two stack items.

OP_2DUP

Duplicates the top two stack items.

OP_3DUP

Duplicates the top three stack items.

OP_2OVER

Copies the pair of items two spaces back to the top.

OP_2ROT

Moves the fifth and sixth items to the top of the stack.

OP_2SWAP

Swaps the top two pairs of items.

OP_IFDUP

Duplicates the top item if it is not zero.

OP_DEPTH

Pushes the number of stack items onto the stack.

OP_DROP

Removes the top stack item.

OP_DUP

Duplicates the top stack item.

OP_NIP

Removes the second‐to‐top stack item.

OP_OVER

Copies the second‐to‐top item to the top of the stack.

OP_PICK

Copies the item n back in the stack to the top.

OP_ROLL

Moves the item n back in the stack to the top.

OP_ROT

Rotates the top three items to the left.

OP_SWAP

Swaps the top two stack items.

OP_TUCK

Copies the top item and inserts it below the second item.

OP_CAT

Disabled opcode; would concatenate two byte strings.

OP_SUBSTR

Disabled opcode; would return a substring of a byte string.

OP_LEFT

Disabled opcode; would return the left part of a byte string.

OP_RIGHT

Disabled opcode; would return the right part of a byte string.

OP_SIZE

Pushes the byte length of the top stack item.

OP_INVERT

Disabled opcode; would flip all bits of the top item.

OP_AND

Disabled opcode; would compute the bitwise AND of two items.

OP_OR

Disabled opcode; would compute the bitwise OR of two items.

OP_XOR

Disabled opcode; would compute the bitwise XOR of two items.

OP_EQUAL

Pushes true if the top two items are equal, otherwise false.

OP_EQUALVERIFY

Runs OP_EQUAL then OP_VERIFY.

OP_RESERVED1

Reserved opcode; makes the transaction invalid if executed.

OP_RESERVED2

Reserved opcode; makes the transaction invalid if executed.

OP_1ADD

Adds 1 to the top item.

OP_1SUB

Subtracts 1 from the top item.

OP_2MUL

Disabled opcode; would multiply the top item by 2.

OP_2DIV

Disabled opcode; would divide the top item by 2.

OP_NEGATE

Negates the sign of the top item.

OP_ABS

Replaces the top item with its absolute value.

OP_NOT

Pushes 1 if the top item is 0, otherwise 0.

OP_0NOTEQUAL

Pushes 0 if the top item is 0, otherwise 1.

OP_ADD

Adds the top two items.

OP_SUB

Subtracts the top item from the second item.

OP_MUL

Disabled opcode; would multiply the top two items.

OP_DIV

Disabled opcode; would divide the second item by the top item.

OP_MOD

Disabled opcode; would compute the remainder of a division.

OP_LSHIFT

Disabled opcode; would shift the second item left.

OP_RSHIFT

Disabled opcode; would shift the second item right.

OP_BOOLAND

Pushes true if both of the top two items are nonzero.

OP_BOOLOR

Pushes true if either of the top two items is nonzero.

OP_NUMEQUAL

Pushes true if the top two numbers are equal.

OP_NUMEQUALVERIFY

Runs OP_NUMEQUAL then OP_VERIFY.

OP_NUMNOTEQUAL

Pushes true if the top two numbers are not equal.

OP_LESSTHAN

Pushes true if the second number is less than the top number.

OP_GREATERTHAN

Pushes true if the second number is greater than the top number.

OP_LESSTHANOREQUAL

Pushes true if the second number is less than or equal to the top.

OP_GREATERTHANOREQUAL

Pushes true if the second number is greater than or equal to the top.

OP_MIN

Pushes the smaller of the top two numbers.

OP_MAX

Pushes the larger of the top two numbers.

OP_WITHIN

Pushes true if the third number is within the range [second, top).]

OP_RIPEMD160

Hashes the top item with RIPEMD‐160.

OP_SHA1

Hashes the top item with SHA‐1.

OP_SHA256

Hashes the top item with SHA‐256.

OP_HASH160

Hashes the top item with SHA‐256 then RIPEMD‐160.

OP_HASH256

Hashes the top item with SHA‐256 twice.

OP_CODESEPARATOR

Marks the point from which the script is signed.

OP_CHECKSIG

Verifies a signature against a public key and pushes the result.

OP_CHECKSIGVERIFY

Runs OP_CHECKSIG then OP_VERIFY.

OP_CHECKMULTISIG

Verifies m signatures against n public keys.

OP_CHECKMULTISIGVERIFY

Runs OP_CHECKMULTISIG then OP_VERIFY.

OP_NOP1

Reserved no‐op opcode for future upgrades.

OP_CHECKLOCKTIMEVERIFY

Marks the transaction invalid if the top item is greater than nLockTime (BIP 65).

OP_NOP2

Former no‐op, now OP_CHECKLOCKTIMEVERIFY.

OP_CHECKSEQUENCEVERIFY

Marks the transaction invalid if the top item is greater than the input sequence (BIP 112).

OP_NOP3

Former no‐op, now OP_CHECKSEQUENCEVERIFY.

OP_NOP4

Reserved no‐op opcode for future upgrades.

OP_NOP5

Reserved no‐op opcode for future upgrades.

OP_NOP6

Reserved no‐op opcode for future upgrades.

OP_NOP7

Reserved no‐op opcode for future upgrades.

OP_NOP8

Reserved no‐op opcode for future upgrades.

OP_NOP9

Reserved no‐op opcode for future upgrades.

OP_NOP10

Reserved no‐op opcode for future upgrades.

OP_CHECKSIGADD

Adds a signature check result to an accumulator (Tapscript, BIP 342).

OP_INVALIDOPCODE

Represents an invalid or unknown opcode.

Name

Description

GetOpName

Returns the mnemonic name of an opcode.

IsOpSuccess

Test for OP_SUCCESSx opcodes as defined by BIP342.

IsPushdataOp

Test whether an opcode is a data‐push operation.