Question 1

What characters need encoding?

Accepted Answer

Spaces, &, =, ?, #, %, +, and most special characters need encoding when used in URL parameters. Letters, numbers, and -, _, ., ~ are safe without encoding.

Question 2

What is the difference between encodeURI and encodeURIComponent?

Accepted Answer

This tool uses encodeURIComponent, which encodes all special characters. encodeURI leaves characters like :, /, and ? intact because they have meaning in URLs.

Question 3

Why does my decoded URL show an error?

Accepted Answer

The input may contain invalid percent-encoded sequences (like %ZZ). Ensure the input is a properly encoded URL string before attempting to decode.

URL Encoder / Decoder