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URL Decoder

Decode URL-encoded strings back to plain text instantly online. Free percent-decoding tool. Supports all encoded characters and Unicode.

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URL Encode

URL-encode any text instantly with percent-encoding. Supports Unicode and all special characters.

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URL decoding reverses percent-encoding, converting sequences like %20 back to spaces, %2F to slashes, and %C3%A9 to the UTF-8 character é. RFC 3986 defines the decoding rules. Developers need to decode URLs when reading logs, debugging redirect chains, inspecting OAuth parameters, or processing form submissions.

Web servers record request URLs in access logs in their encoded form. Analytics platforms, CDN logs (Cloudflare, Fastly), and NGINX access logs all contain percent-encoded query strings and paths. Decoding is required to read search terms, tracking parameters, or file paths that were submitted by users or constructed by client-side JavaScript.

This tool decodes percent-encoded strings using JavaScript's decodeURIComponent() function, which handles the full UTF-8 multibyte decoding needed for non-ASCII characters. It is the correct inverse of encodeURIComponent() and properly decodes all percent-encoded sequences including multibyte UTF-8 characters like emoji and accented letters.

Common Use Cases

Reading encoded query strings in server logs

NGINX and Apache access logs record URLs exactly as received, with all special characters percent-encoded. A search request appears as /search?q=machine%20learning%20%26%20AI rather than readable text. Decoding these log lines is essential when analyzing search traffic, debugging 404 errors, or auditing what terms users actually searched for.

Debugging OAuth redirect parameters

OAuth 2.0 error responses and authorization callbacks pass state tokens, error descriptions, and redirect URIs as percent-encoded query parameters. When an OAuth flow breaks in production, inspecting the raw callback URL requires decoding to read the error_description and state values that explain what went wrong in the authorization server.

Extracting file names from download URLs

CDN and presigned download URLs from AWS S3, Azure Blob Storage, or Google Cloud Storage embed the object key — including folder paths with spaces and Unicode filenames — in percent-encoded form. Decoding the URL reveals the actual file path and name, which is needed when building download managers or auditing storage access logs.

Processing HTML form submissions

HTML forms submitted with method=GET append field values as percent-encoded query strings. When testing form behavior with curl or reading raw HTTP request logs from a web application firewall (WAF), decoding the query string reveals the actual submitted values, making it possible to reproduce the request and debug validation logic.

How to Use the URL Decoder

  1. Paste your URL-encoded string in the left panel.
  2. The decoded text appears instantly in the right panel.
  3. Click "Copy Output" to copy the decoded result.
  4. Use "Load Example" to see a sample decoding.

Common Use Cases