OP_ENDIF ​

OP_ENDIF is used to conclude conditional structures in Bitcoin scripting initiated by OP_IF or OP_NOTIF. It denotes the end of the conditional execution paths and allows the script to continue with any subsequent commands outside of the conditional block.

Operation ​

1. Continue executing the following opcodes in the script after the OP_ENDIF.

Note that OP_ENDIF itself does not directly cause any action other than marking the end of the conditional segment. Its presence ensures that the preceding conditional logic (whether that's an OP_IF, OP_NOTIF, or an accompanying OP_ELSE) has been properly closed.

Notes ​

• Each OP_IF or OP_NOTIF must have a corresponding OP_ENDIF. Failing to do so will render the script invalid.
• A script can have nested OP_IF/OP_NOTIF structures, but each of them must be properly closed with their own OP_ENDIF.
• A script with an OP_ENDIF without a preceding OP_IF or OP_NOTIF is also invalid.

Examples ​

Example 1 ​

The following script leaves 2 on the stack since the condition (1) is true.

# ASM script
OP_1 OP_IF OP_2 OP_ENDIF

# Raw script
516368

# Final stack
2

Example 2 ​

The following script with nested conditionals leaves 4 on the stack since both conditions (1) are true.

# ASM script
OP_1 OP_IF 
    OP_1 OP_IF 
        OP_4 
    OP_ENDIF
OP_ENDIF

# Raw script
51516351546868

# Final stack
4