Opcodes · stack · enabled

OP_2DUP (0x6e)

Duplicates the top two items.

Verified
Stack in → out
a b → a b a b
Since
Original Bitcoin script
Cost
Base instruction cost 100 plus bytes pushed (2025 VM limits).
Bitcoin status
Same in Bitcoin (BTC)

Example

OP_1 OP_2 OP_2DUP

Step through it opcode by opcode in Bitauth IDE, the in-browser BCH VM debugger.

Sources

  1. Libauth BCH_2023_05 opcodes (bch-2023-opcodes.ts)