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URL encoder

Two rules, and picking the wrong one is the reason most links break.

The note under the switch says what each rule does to the characters that give a URL its structure.

Direction
Rule

Escapes everything that is not a plain letter, digit or one of - _ . ! ~ * ' ( ), including / : ? & =. Use this for a value going inside a URL, like a search term or a redirect target.

Result

Questions

Is what I paste sent anywhere?
No. Every tool in this kit runs in the page itself. There is no server here that receives what you paste, and you can check it in your browser's network tab: using a tool produces no request carrying your input at all.
What is the difference between the two rules?
The component rule escapes everything that is not a plain letter, digit or one of a few marks, including the slash, colon, question mark, ampersand and equals. Use it for a value going inside a URL. The whole URL rule leaves those structural characters alone. Use it for a URL that only needs its spaces and accents made safe.
What happens if I pick the wrong one?
Escaping a whole URL with the component rule turns every slash into %2F and produces a link that goes nowhere. Escaping a query value with the whole URL rule leaves an ampersand intact, which splits your own parameter in two at the other end.
Why does decoding sometimes fail?
Because a percent sign that is not followed by two hex digits is not valid in a URL. A literal percent has to be written %25. The tool says so rather than throwing.

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