URL encode / decode
Convert text to and from percent-encoding, in your browser.
This URL encode and decode tool converts text to and from percent-encoding, the format that keeps URLs valid when they contain spaces, ampersands, or other reserved characters. Encoding replaces unsafe characters with a percent sign followed by their hex code, so a space becomes %20 and a query string survives transmission intact. Decoding reverses the process to show the human-readable original. Paste a string, choose a direction, and the result updates instantly without anything leaving your browser.
Frequently asked questions
What's the difference between encoding a full URL and a single parameter?
A whole URL keeps characters like slashes and colons intact, while a single parameter value should encode them. This tool does component-style encoding for safe parameter values.
Why do spaces sometimes become + instead of %20?
The + convention comes from form submissions, while %20 is standard in URL paths. Both decode back to a space in the right context.
Is it safe to paste sensitive query strings here?
Yes. All encoding and decoding happens locally in your browser and nothing is uploaded.
Which characters need to be percent-encoded?
Reserved characters (like ?, &, =, #, /, and spaces) and any non-ASCII text must be encoded inside a parameter value, while unreserved letters, digits, and a few symbols stay as-is. Encoding only the value keeps the URL's structure intact.
What is double encoding and why does it break things?
Double encoding is when an already-encoded string gets encoded again, turning %20 into %2520. It usually happens when a value passes through two layers that each encode it; decode once at each layer to fix it.
Why did decoding turn my %2B into a plus sign?
That's correct — %2B is the encoding for a literal +. A raw + in a query string can be interpreted as a space, which is exactly why a literal plus must be encoded as %2B.
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