index.md

---

title: Extend
slug: WebAssembly/Reference/Numeric/Extend

---

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The extend instructions, are used to convert (extend) numbers of type i32 to type i64. There are signed and unsigned versions of this instruction.

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Syntax

;; push an i32 onto the stack
i32.const 10

;; sign-extend from i32 to i64
i64.extend_i32_s

;; the top item on the stack will now be the value 10 of type i64

Instruction	Binary opcode
i64.extend_i32_s	0xac
i64.extend_i32_u	0xad