What is URL encoding (percent-encoding)?

It's a method of representing characters that aren't allowed directly in a URL — like spaces, &, ?, #, and non-ASCII characters — as a percent sign followed by two hexadecimal digits representing the character's byte value, e.g. a space becomes %20.

When do I need to URL-encode text?

Any time you're building a URL, query string, or form submission that includes user-generated text, special characters, or non-English text. Search queries, redirect URLs, and API parameters passed in a URL all commonly need encoding.

What's the difference between encodeURIComponent and encodeURI?

encodeURIComponent (what this tool uses) encodes every character that isn't safe inside a single URL component like a query parameter value, including &, =, and /. encodeURI is meant for encoding an entire URL and leaves those structural characters untouched. Use encodeURIComponent when encoding a value that will go inside a query string.

Why does decoding sometimes show an error?

Decoding fails when the input contains a malformed percent-encoded sequence — for example, a '%' not followed by two valid hexadecimal digits, or a sequence that doesn't form valid UTF-8 bytes. This tool catches that URIError and displays a clear message instead of crashing.

Does this handle spaces correctly?

Yes. A space is encoded as %20 by encodeURIComponent (the correct form for a URL path or query value). Note that HTML form submissions using application/x-www-form-urlencoded traditionally use '+' for spaces instead — that's a distinct convention this tool does not replicate.

Can this tool handle emoji and non-Latin text?

Yes. encodeURIComponent first UTF-8-encodes the text, then percent-encodes each resulting byte, so emoji, Chinese, Arabic, and other Unicode text round-trip correctly through encode and decode.

Is my data sent to a server when I use this tool?

No. Encoding and decoding both run entirely in JavaScript inside your browser tab using built-in browser APIs. No network request is made.

What are 'reserved characters' in a URL?

Characters like : / ? # [ ] @ ! $ & ' ( ) * + , ; = have special meaning in URL syntax (separating the scheme, path, query, and fragment). encodeURIComponent escapes these so they're treated as literal data rather than structural URL syntax when placed inside a component like a query value.

Why is my encoded URL so much longer than the original text?

Every character outside the small 'unreserved' set (letters, digits, - _ . ~) gets replaced with a 3-character %XX sequence per UTF-8 byte. Text with many spaces, symbols, or non-ASCII characters can expand significantly.

Can I use this for encoding a full URL, not just a query parameter?

This tool is built around encodeURIComponent, intended for encoding individual URL components (like a single query parameter value), not an entire URL with its scheme and path structure — encoding a full URL this way would also escape the ':' and '/' characters that need to stay literal.

URL Encoder & Decoder — Percent-Encode or Decode URLs Instantly

Our URL Encoder / Decoder converts text to and from percent-encoding (the %XX format used in URLs and query strings) using the browser's native encodeURIComponent and decodeURIComponent functions. Toggle between Encode and Decode mode, type or paste your text, and see the result update instantly. Malformed percent-encoded sequences on decode are caught and reported clearly instead of crashing. Everything happens locally — no text is ever sent to a server.

Text to encode

Result

Your encoded or decoded result will appear here

How to Use the URL Encoder / Decoder — Free Online Percent-Encoding Tool

1
Choose Encode to percent-encode text for safe use in a URL, or Decode to convert a percent-encoded string back to plain text.
2
Paste or type your input into the text area.
3
The result appears instantly below as you type — no button click required.
4
Click 'Copy' to copy the encoded or decoded result to your clipboard.

Why Use URL Encoder / Decoder — Free Online Percent-Encoding Tool?

URLs can only safely contain a limited set of characters — letters, digits, and a handful of punctuation marks. Spaces, ampersands, question marks, and non-ASCII characters like accented letters or emoji must be percent-encoded (represented as %XX, where XX is the character's hex byte value) before they can be safely included in a URL path, query string, or form submission. Without correct encoding, URLs break, query parameters get truncated at unescaped '&' or '=' characters, and non-ASCII text becomes garbled. This tool uses JavaScript's built-in encodeURIComponent, which correctly UTF-8-encodes Unicode text before percent-encoding it, and decodeURIComponent, which reverses the process. Decoding a malformed percent-encoded string (like a lone '%' not followed by two hex digits) normally throws a URIError — this tool catches that and shows a readable error instead of crashing.

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