UlvixorURL Encoder & Decoder
Encode text so it can be safely used as part of a URL (for example, in a query parameter), or decode already-encoded text to read it in plain form. Uses encodeURIComponent/decodeURIComponent, processed entirely in your browser.
How it works
- Choose the 'Encode' or 'Decode' tab depending on what you need.
- Paste or type the text into the input panel.
- The result is generated instantly using encodeURIComponent or decodeURIComponent, JavaScript's native functions.
- If the text you're decoding contains malformed %XX sequences, you'll see a clear error instead of an incorrect result.
- Copy the result or download it as a text file.
Use cases
- Encode values to include as query parameters in a URL (?search=...).
- Decode URL parameters found in logs, redirects, or webhooks to read them in plain form.
- Encode special characters, spaces, or symbols before manually building a URL.
- Debug encoding issues when integrating with APIs that receive data via query string.
Use cases
- Encode values to include as query parameters in a URL (?search=...).
- Decode URL parameters found in logs, redirects, or webhooks to read them in plain form.
- Encode special characters, spaces, or symbols before manually building a URL.
- Debug encoding issues when integrating with APIs that receive data via query string.
Common mistakes
- Using encodeURI instead of encodeURIComponent for a single value.encodeURI doesn't encode characters like &, =, ?, or /, so it can break the URL's structure if they appear inside a parameter. For a single value, use encodeURIComponent, which is what this tool does.
- Encoding the entire URL instead of just the parameter value.If you encode the whole URL, the structural characters (://, ?, &) get encoded too and the URL stops working. Encode only the value, not the entire URL.
- Decoding text with a stray % symbol that isn't part of a valid code.The tool detects the malformed %XX sequence and shows an error instead of an incorrect result.
Frequently asked questions
encodeURIComponent encodes nearly all special characters, including &, =, ?, /, and #, which makes it the right function for encoding a single value that will go inside a query parameter or path segment. encodeURI, on the other hand, is meant for encoding a complete URL, and it leaves characters like &, =, ?, and / untouched because they're part of the URL's syntax. This tool uses encodeURIComponent (component encoding), not encodeURI.
No. All encoding and decoding happen locally in your browser using JavaScript's native functions. Your text never leaves your device.
If the text contains incomplete or invalid %XX escape sequences, decodeURIComponent throws an error (URIError), which the tool catches and displays as a clear message instead of failing silently or showing corrupted text.
It's not ideal. This tool encodes every special character, including ones that are part of a URL's structure (like :, /, or ?). Use it to encode a single value (for example, search text) that you'll then insert yourself into the full URL.
Alternatives
In code, almost every language offers its own equivalent function (urllib.parse.quote in Python, encodeURIComponent in JavaScript). This tool is handy for a quick encoding without opening an interpreter.