tooloora

URL Encode & Decode — percent-encoding, local

Percent-encode text for URLs or decode it back, instantly in your browser — nothing is uploaded.

Runs locally — nothing is uploaded

Runs locally in your browser — no upload.

Encode and decode URLs in your browser

Paste text to percent-encode it for a URL, or paste an encoded string to decode it back — the result updates as you type. Choose whether to encode a single value or a whole URL, switch direction with one click, and copy the result. Everything runs in your browser: no upload, no signup, offline-capable.

What is URL encoding?

A URL may only contain a limited set of ASCII characters (RFC 3986). Percent-encoding replaces every other character with % followed by its byte value in hex — a space becomes %20, & becomes %26, ä becomes %C3%A4. This is what lets search queries, parameters and file names with spaces or symbols travel inside a link without breaking it.

Encode a value vs. a whole URL

  • Encode value (encodeURIComponent) escapes everything, including & = ? / :. Use it for one query parameter value or a single path segment.
  • Encode whole URL (encodeURI) keeps the characters that give a URL its structure (& = ? / : #). Use it for a complete address that just needs its spaces and accents escaped.

Picking the wrong one is a common bug: encoding a full URL with the "value" mode turns its ? and & into %3F and %26, breaking the link.

Decoding and error handling

Decoding turns %XX sequences back into characters. If the input contains a malformed sequence — a lone % or an invalid code like %ZZ — the tool shows an error instead of guessing, so you never copy a silently wrong result.

Private by default

Your input is encoded and decoded locally with your device's own resources. Confidential URLs, tokens and parameters are never sent to a server — the tool even works in airplane mode.

Frequently asked questions

What is URL (percent) encoding?

URLs may only contain a limited set of characters. Percent-encoding replaces unsafe characters with a % followed by their hex code — a space becomes %20, an ampersand %26. This lets spaces, accents and symbols travel safely inside a URL or query string.

What's the difference between the two modes?

‘Encode value’ uses encodeURIComponent and escapes everything, including & = ? / — use it for a single query value or path segment. ‘Encode whole URL’ uses encodeURI and keeps URL structure characters (& = ? / : #) intact — use it for a complete address.

Is my input uploaded anywhere?

No. Encoding and decoding happen entirely in your browser. Nothing is sent to a server, so confidential URLs and tokens stay on your device — it works offline too.

Why does decoding sometimes fail?

Decoding fails when the input contains a malformed percent sequence, such as a lone % or %ZZ that isn't a valid hex code. The tool shows an error instead of returning a wrong result so you can fix the input.

Does it handle UTF-8 characters?

Yes. Multi-byte characters like ä or emoji are encoded as several %XX bytes and decoded back exactly, so nothing is lost in the round trip.