index.md

---

title: Wrap
slug: WebAssembly/Reference/Numeric/Wrap

---

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The wrap instruction, is used to convert numbers of type i64 to type i32. If the number is larger than what an i32 can hold this operation will wrap, resulting in a different number.

One can think of wrap either as reducing the value mod 2³², or as discarding the high 32 bits to produce a value containing just the low 32 bits.

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Syntax

;; push an i64 onto the stack
i64.const 10

;; wrap from i64 to i32
i32.wrap_i64

;; the top item on the stack will now be the value 10 of type `i32`

Instruction	Binary opcode
i32.wrap_i64	0xa7