URL Encoder/Decoder

URLs may only contain a limited set of characters. Anything else, including spaces, ampersands, question marks and every accented or non-Latin letter, has to be percent-encoded to travel safely. That is why a space becomes %20 and why a link with an unencoded ampersand in a parameter value truncates and breaks.

The failure mode is quiet. A tracking parameter carrying a campaign name with a space or a plus sign will look fine in an email and arrive at the server mangled, so the analytics attribution silently disappears. Encoding the value first prevents it, and decoding an existing URL shows you what a long, opaque link is really carrying.

Developers encode query parameters and redirect targets; marketers encode campaign values in UTM strings; support staff decode links from tickets to see what a customer actually clicked. Both directions run locally in your browser, so URLs containing session identifiers or personal data are not sent anywhere.

How to use the URL Encoder/Decoder

1. Paste the URL or the parameter value into the input box.
2. Choose encode to make it safe, or decode to make it readable.
3. Read the result in the output area.
4. Encode individual parameter values rather than a whole assembled URL where possible.
5. Copy the output into your link, code or documentation.

Examples

• A marketer encodes a campaign name containing spaces so a UTM parameter survives intact.
• A developer encodes a redirect target that itself contains a query string.
• A support agent decodes a long link from a ticket to see which product the customer was viewing.

Frequently asked questions

Why does a space sometimes become a plus sign?

Form submissions historically encode spaces as plus signs in the query string, while percent-encoding uses %20. Both appear in the wild.

Should I encode the whole URL?

No. Encoding the entire URL would escape the slashes and colons that give it structure. Encode individual parameter values instead.

How are non-Latin characters handled?

They are encoded as UTF-8 byte sequences, which is why a single accented character can become several percent-encoded pairs.

Is double encoding a problem?

Yes. Encoding an already encoded string turns each percent sign into %25, producing a link that decodes to the wrong value.

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