What Is URL Decoding?
URL decoding is the reverse of URL encoding. It converts percent-encoded characters (like %20 for spaces, %26 for ampersands) back to their original characters, making URLs and query parameters human-readable again.
When Do You Need URL Decoding?
- Reading query parameters — Extracting user input from URL query strings.
- Debugging URLs — Making encoded URLs readable for troubleshooting.
- Processing form data — Decoding
application/x-www-form-urlencodedsubmissions. - Log analysis — Reading server logs that contain encoded URLs.
Frequently Asked Questions
Can URL decoding fail?
Yes, if the input contains invalid percent-encoding sequences (e.g., %ZZ) or truncated sequences (e.g., %2 without the second hex digit), decoding will fail.