URL encoding explained: encode and decode query strings safely

Spaces, ampersands and non-English letters cannot sit raw inside a web address. They are replaced with a percent sign and two hex digits, such as %20 for a space. URL encode/decode does this for you.

Steps

1. Paste your text or URL.
2. Choose the Action: encode a component, encode a whole URI, or decode.
3. Copy the result.

Component or whole URI?

• Component encodes almost everything special: a b&c becomes a%20b%26c. Use it for a value that goes into a query string.
• Whole URI keeps the structure characters such as :, /, ? and = and only encodes unsafe ones: https://x.com/a b?q=1 becomes https://x.com/a%20b?q=1.

Encoding a whole URL as a component would break it, because the slashes and colons would be encoded too.

Decoding

Decoding turns %20 back into spaces and %E0%A4%A8 into Unicode characters. A broken sequence, such as a lone %E0%A4%A, gives an error message instead of garbage.

Tips

• Encode each value separately, then join with &.
• Double encoding (%2520) means something was encoded twice; decode once and check.
• Keep + in mind: in forms it can mean a space, but in a path it is a literal plus.