What this tool does
URL Encode / Decode converts between plain text and percent-encoding: characters that are special inside URLs — Chinese, spaces, &, = — must be escaped before they are safe in query strings or redirect URIs.
Same shuttle UI as our Base64 tool: paste plain text on the left and encode, paste an encoded string on the right and decode, one click to copy. Everything runs in your browser; nothing is uploaded.
How to use
- Paste plain text, click Encode Spaces become %20 and Chinese becomes %E4%B8%AD-style UTF-8 byte sequences.
- Paste encoded text, click Decode Invalid % sequences fail loudly instead of silently, so bad data is easy to spot.
- Enable "+ as space" for form data HTML forms (application/x-www-form-urlencoded) encode spaces as +; enable the toggle to decode those.
FAQ
Do spaces become + or %20?
Encoding always emits %20. Only legacy form data uses +; enable the toggle when decoding that.
How is this different from encodeURI?
encodeURI keeps URL structure characters; this tool treats input as a parameter value and escapes them too.
What does a decode error mean?
The data is broken: usually a missing hex pair after %, or a truncated UTF-8 byte sequence.
Is my text uploaded?
No. Encoding and decoding happen entirely in your browser.
Can I drop a file?
Yes. A dropped .txt is auto-routed: %XX sequences go right, otherwise left.
What do Chinese characters become?
UTF-8 bytes, escaped: 中 becomes %E4%B8%AD — three bytes, nine characters.
Limits
Up to 10MB per file; UTF-8 text only.
No encodeURI mode, no IDN/punycode domain conversion.
Decoding never fails silently: broken data errors out.