decodeURI
Decodes a Uniform Resource Identifier previously created by encodeURI or by a similar routine
Syntax
decodeURI(encodedURI)Parameters
| Parameter | Type | Description |
|---|---|---|
| encodedURI | string | A complete, encoded URI |
Return Value
A new string representing the unencoded version of the encoded URI
Examples
const encoded = 'https://example.com/path%20with%20spaces';
console.log(decodeURI(encoded));
// 'https://example.com/path with spaces'const uri = 'https://example.com/%E4%B8%AD%E6%96%87';
console.log(decodeURI(uri)); // 'https://example.com/中文'try {
decodeURI('%E0%A4%A'); // malformed
} catch (err) {
console.log(err instanceof URIError); // true
}Understanding decodeURI
The decodeURI method in JavaScript decodes a Uniform Resource Identifier previously created by encodeURI or by a similar routine. It belongs to the window object and is one of the most widely used methods for working with window values in modern JavaScript and TypeScript applications.
The method signature is decodeURI(encodedURI). It accepts 1 parameter: encodedURI. When called, it returns a new string representing the unencoded version of the encoded uri. Understanding when and how to use decodeURI() helps you write more expressive, readable code.
Common use cases for decodeURI include data transformation, input validation, API response processing, and building reusable utility functions. It works well alongside related methods like window-encodeuri, window-decodeuricomponent, window-encodeuricomponent, enabling you to chain operations together for complex data manipulation pipelines.
Browser support for decodeURI is excellent across all modern browsers including Chrome, Firefox, Safari, and Edge. It is also fully supported in Node.js and Deno. For older environments, transpilation with Babel or a polyfill may be needed.
Browser Compatibility
Supported in all modern browsers (Chrome, Firefox, Safari, Edge) and Node.js. Part of the ECMAScript standard.
Related Methods
encodeURIEncodes a URI by replacing certain characters with UTF-8 escape sequences, but preserves characters that are part of URI syntax
decodeURIComponentDecodes a URI component previously created by encodeURIComponent or by a similar routine
encodeURIComponentEncodes a URI component by replacing certain characters with UTF-8 escape sequences
More Global / Window Methods
Other methods in the Global / Window object
Related Tools
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