What is the difference between whole-URL and component mode?

Whole-URL mode (encodeURI) keeps characters that are legal in a URL like : / ? & # intact, so a full address stays usable. Component mode (encodeURIComponent) encodes those too, which is what you need for a single query-string value or path segment.

Why does a space become %20 or +?

Percent-encoding represents a space as %20. The + form is specific to application/x-www-form-urlencoded form data. This tool uses standard %20 percent-encoding.

No. Encoding and decoding run in your browser. Nothing is sent to a server.

URL Encoder & Decoder

Percent-encode and decode URLs and query parameters, with whole-URL or single-component modes and full Unicode. Everything runs in your browser — nothing is uploaded.

Input

Output

Component mode — encode : / ? & # too (for one query value)

When you need URL encoding

URLs may only contain a limited set of characters. Anything else — spaces, accents, ampersands inside a value, emoji — must be percent-encoded (e.g. a space becomes %20). You'll reach for this when building links by hand, debugging an API call, pasting a tracking URL, or decoding a redirect to see where it actually points.

Whole URL vs single component

Use whole-URL mode to encode an entire address while keeping its structure (: / ? & #) intact. Switch to component mode when you're encoding a single query-string value or path segment, where those separators must also be escaped so they aren't mistaken for structure.

Private by design. Encoding and decoding happen in your browser. Nothing is uploaded.

Frequently asked questions

Whole-URL vs component mode?

Whole-URL keeps : / ? & #; component mode encodes them too, for a single value.

Why %20 instead of +?

%20 is standard percent-encoding for a space. The + form is only for form-encoded bodies.

Is my text uploaded?

No — it runs entirely in your browser.

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