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String.prototype.padStart() - JavaScript | MDN
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String.prototype.padStart()

Baseline Widely available

This feature is well established and works across many devices and browser versions. Its been available across browsers since 20174.

:

padStart() ()

In this article

Syntax

js
str.padStart(targetLength [, padString])

Parameters

targetLength

padString

" " (U+0020).

Return value

Examples

js
"abc".padStart(10); // "       abc"
"abc".padStart(10, "foo"); // "foofoofabc"
"abc".padStart(6, "123465"); // "123abc"

Specification
ECMAScript 2027 LanguageSpecification
# sec-string.prototype.padstart

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