Nullish coalescing
The nullish coalescing (??) and nullish coalescing assignment (??=) operators return (or assign) its right-hand side operand when its left-hand side operand is null or undefined, and otherwise returns its left-hand side operand.
Status
Baseline Widely Available (since 2023-03-16)
MDN documentation
Specifications
- ECMAScript® 2026 Language Specification (#prod-CoalesceExpression), from TC39 (Ecma International).
Browser support
- Chrome 85 Released on 2020-08-25
- Chrome Android 85 Released on 2020-08-25
- Edge 85 Released on 2020-08-27
- Firefox 79 Released on 2020-07-28
- Firefox for Android 79 Released on 2020-07-28
- Safari 14 Released on 2020-09-16
- Safari on iOS 14 Released on 2020-09-16
Developer signals
- State of JS 2025: features/syntax_features question
Usage (according to Chrome Platform Status)
~37.204% of page loads. More data at chromestatus.com.
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