URL encoder / decoder

A query string that breaks without encoding

Say you want q=nails & tips as a search value. If you paste that raw into a URL, the & starts a new parameter and the space splits the request. Component mode turns the value into something a parser can treat as one field:

Build the URL as ?q= plus the encoded value, not by encoding the whole ?q=... string in component mode (that would encode the ? and = too).

Component vs full URL

Component matches encodeURIComponent / decodeURIComponent. Use it for one value you will drop into a query string, path segment, or header that expects a single token.

Full URL matches encodeURI / decodeURI. It escapes spaces and non-ASCII characters but leaves structural characters alone: :/?#[]@!$&'()*+,;=. Reach for it when the input is already shaped like https://example.com/path?x=1 and you only need the unsafe bits percent-encoded.

Wrong scope is a common bug: full-URL encode on a lonely a&b leaves the & untouched, which is usually not what you wanted for a query value.

Spaces, plus signs, and form bodies

This tool follows the JavaScript URL APIs: spaces become %20, and + stays +. HTML form encoding (application/x-www-form-urlencoded) historically used + for spaces. If you are talking to an API that still expects that dialect, encode with component mode, then replace %20 with + for that hop only. Decode the other way: turn + into a space before decodeURIComponent when the peer used form encoding.

What this page will not do

• Upload or log your string (no server round-trip).
• Parse or rebuild a full URL object graph. For query editing beyond encode/decode, use a dedicated URL builder.
• Base64 or JWT work. For payloads in Base64 see the Base64 encoder; for HS256 tokens see the JWT encoder.
• Guess which dialect a remote API wants. Check the docs for %20 vs + and for whether reserved characters should stay literal.

FAQ