Remainder assignment (%=)
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The remainder assignment (%=
) operator performs remainder on the two operands and assigns the result to the left operand.
Try it
let a = 3;
console.log((a %= 2));
// Expected output: 1
console.log((a %= 0));
// Expected output: NaN
console.log((a %= "hello"));
// Expected output: NaN
Syntax
js
x %= y
Description
x %= y
is equivalent to x = x % y
, except that the expression x
is only evaluated once.
Examples
Using remainder assignment
js
let bar = 5;
bar %= 2; // 1
bar %= "foo"; // NaN
bar %= 0; // NaN
let foo = 3n;
foo %= 2n; // 1n
Specifications
Specification |
---|
ECMAScript® 2025 Language Specification # sec-assignment-operators |
Browser compatibility
Report problems with this compatibility data on GitHubdesktop | mobile | server | ||||||||||||
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Remainder assignment ( x %= y ) |
Legend
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- Full support
- Full support
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.