Question 1

What is URL encoding (percent encoding)?

Accepted Answer

URL encoding replaces unsafe or reserved characters in a URL with a '%' followed by two hexadecimal digits. For example, a space becomes '%20' and an ampersand becomes '%26'. This is required because URLs can only contain a subset of ASCII characters — anything outside that set must be encoded.

Question 2

When should I URL-encode a string?

Accepted Answer

URL-encode any value you're putting into a URL query string, path segment, or form data. For example, if your query parameter value contains a space, '&', '=', or non-ASCII characters, you must encode them. Most programming languages do this automatically, but if you're constructing URLs manually, use this tool.

Question 3

What's the difference between URL encoding and URI encoding?

Accepted Answer

They're essentially the same thing — URL encoding is a subset of URI encoding. The terms are often used interchangeably. RFC 3986 defines the modern standard. JavaScript's encodeURIComponent() encodes more characters than encodeURI() (which leaves URL-reserved characters like '/', '?', '&' alone).

Question 4

Can URL encoding be reversed?

Accepted Answer

Yes, URL encoding is fully reversible — it's an encoding, not encryption. Paste any URL-encoded string into the decoder above and the original text appears. This is required for processing URL parameters in web applications.

URL Encoder & Decoder

URL Encode/Decode

How to use this tool

Frequently Asked Questions

URL Encode/Decode

How to use this tool

Frequently Asked Questions

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