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Symbol.search

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨January 2020⁩.

The Symbol.search static data property represents the well-known symbol Symbol.search. The String.prototype.search() method looks up this symbol on its first argument for the method that returns the index within a string that matches the current object.

For more information, see RegExp.prototype[Symbol.search]() and String.prototype.search().

Try it

class Search1 {
  constructor(value) {
    this.value = value;
  }
  [Symbol.search](string) {
    return string.indexOf(this.value);
  }
}

console.log("foobar".search(new Search1("bar")));
// Expected output: 3

Value

The well-known symbol Symbol.search.

Property attributes of `Symbol.search`
Writable	no
Enumerable	no
Configurable	no

Examples

Custom string search

class CaseInsensitiveSearch {
  constructor(value) {
    this.value = value.toLowerCase();
  }
  [Symbol.search](string) {
    return string.toLowerCase().indexOf(this.value);
  }
}

console.log("foobar".search(new CaseInsensitiveSearch("BaR"))); // 3

Specifications

Specification
ECMAScript® 2026 Language Specification> # sec-symbol.search>

Browser compatibility

	Desktop					Mobile							Server
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet	WebView Android	WebView on iOS	Bun	Deno	Node.js
`search`	50	79	49	37	10	50	49	37	10	5.0	50	10	1.0.0	1.0	6.0.0