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decodeURI() - JavaScript | MDN
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decodeURI()

Baseline Widely available

This feature is well established and works across many devices and browser versions. Its been available across browsers since 2015 7.

decodeURI() encodeURI URI(Uniform Resource Identifier, ) .

In this article

const uri = "https://mozilla.org/?x=";
const encoded = encodeURI(uri);
console.log(encoded);
// Expected output: "https://mozilla.org/?x=%D1%88%D0%B5%D0%BB%D0%BB%D1%8B"

try {
  console.log(decodeURI(encoded));
  // Expected output: "https://mozilla.org/?x="
} catch (e) {
  // Catches a malformed URI
  console.error(e);
}

js
decodeURI(encodedURI)

encodedURI

(URI)

URI .

encodedURI URIError ("malformed URI sequence") .

URI () encodeURI . # .

URL

js
decodeURI(
  "https://developer.mozilla.org/ru/docs/JavaScript_%D1%88%D0%B5%D0%BB%D0%BB%D1%8B",
);
// "https://developer.mozilla.org/ru/docs/JavaScript_"

js
try {
  var a = decodeURI("%E0%A4%A");
} catch (e) {
  console.error(e);
}

// URIError: malformed URI sequence

Specification
ECMAScript 2027 LanguageSpecification
# sec-decodeuri-encodeduri

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