URL Encoder & Decoder

What is URL encoding?

URL encoding (also called percent-encoding) converts special characters into a safe format that can be transported in a URL. For example, a space becomes %20, and reserved characters like ? or & are encoded when they are part of the value rather than the URL structure.

Encode vs decode

Encode URL

Use encoding when you’re inserting user input into a query parameter, building links programmatically, or generating redirect URLs. Encoding prevents broken links caused by spaces, unicode characters, or reserved symbols.

Decode URL

Use decoding when you need to read or debug a URL-encoded string (for example, a query string value copied from logs). Decoding converts sequences like %2F back into readable characters.

Common use cases

• Query strings: safely encode values like names, search queries, and filters.
• Debugging: decode redirect targets or callback URLs to inspect what’s being sent.
• APIs: encode path/query inputs to avoid invalid requests.

Error handling (why decoding can fail)

Decoding requires valid percent-encoding. If the input contains malformed sequences (for example, a % not followed by two hex digits), browsers throw an error. This tool displays an error message so you can spot and fix invalid encoding quickly.

Privacy and performance

The encoder/decoder runs locally in your browser. That keeps it fast and avoids sending your URLs or query values to a server for processing.