Question 1

When should I use encodeURIComponent vs encodeURI?

Accepted Answer

Use encodeURIComponent for individual values like a single query parameter — it encodes characters such as &, =, and ?. Use encodeURI for a complete URL, where those characters must stay intact.

Question 2

Why are spaces shown as %20 or +?

Accepted Answer

Percent-encoding represents a space as %20. In query strings, a space is sometimes encoded as + instead; both decode back to a space.

Question 3

Is my data sent anywhere?

Accepted Answer

No. Encoding, decoding, and URL parsing all happen in your browser. Nothing is uploaded.

Question 4

Which characters get encoded?

Accepted Answer

Reserved and unsafe characters (spaces, /, ?, #, &, =, non-ASCII, and more) are converted to %XX sequences so the URL stays valid.

Question 5

Can it parse a URL into parts?

Accepted Answer

Yes. The URL breakdown shows the protocol, host, port, path, query parameters, and fragment separately.

URLEncoder / Decoder

URL
Encoder / Decoder