URL Encoder / Decoder
Percent-encodes and decodes text and query strings for use in URLs.
Designed to process your files locally in your browser. Zerdly does not intentionally upload or store them unless this page says otherwise.
How to use this calculator
- Paste a URL or text.
- Press Encode or Decode.
How it works
URL (percent) encoding replaces characters that aren't safe in a web address with a % sign and their hex code — a space becomes %20, an ampersand %26. Decoding reverses it.
Worked example
"a b&c". encodes to a%20b%26c.
Common mistakes
- Encoding a whole URL when you only meant a query value — encoding the ? and / can break the link.
- Forgetting that spaces become %20 (or + in form data), which trips up manual edits.
Frequently asked questions
When do I need to URL-encode text?
Whenever a value goes into a URL and contains spaces or symbols like &, ?, = or /, encoding stops them being misread as part of the address.
Is my data sent anywhere?
No — encoding and decoding happen locally in your browser, so nothing leaves your device.
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Cite this tool
Zerdly. (2026). URL Encoder / Decoder. Retrieved from https://www.zerdly.com/tools/url-encoder-decoder/
Tip: Enter any known values to calculate the remaining results.
Designed to run locally in your browser. Tool inputs are not intentionally stored by Zerdly unless stated otherwise.