String.prototype.startsWith() - JavaScript | MDN

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coerced to strings

The characters to be searched for at the start of this string. Cannot be a regex. All values that are not regexes are coerced to strings, so omitting it or passing undefined causes startsWith() to search for the string "

String.prototype.endsWith()

String.prototype.includes()

String.prototype.indexOf()

String.prototype.lastIndexOf()

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This page was last modified on Jul 20, 2025 by MDN contributors.

toLocaleLowerCase()

toLocaleUpperCase()

[Symbol.iterator]()

[Symbol.hasInstance]()

__defineGetter__()

__defineSetter__()

__lookupGetter__()

__lookupSetter__()

propertyIsEnumerable()

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