What does the form variant change?

application/x-www-form-urlencoded is what browsers use for form submissions and URLSearchParams: space becomes + instead of %20, and * - . _ stay bare. When decoding, + turns back into a space.

When do I need RFC 3986 strict encoding?

encodeURIComponent leaves ! ' ( ) * unencoded even though RFC 3986 reserves them. OAuth 1.0 signatures and some strict servers require them encoded — the strict variant does that.

How does the decoder handle double-encoded strings?

It decodes repeatedly until the string stops changing and reports the number of layers. Turn "Decode all layers" off to unwrap a single layer at a time.

Why does decoding say the escapes are not valid UTF-8?

A sequence like %E9 on its own is Latin-1, not UTF-8 (which needs %C3%A9). The decoder tells you the position so you can fix the byte sequence.

Can I edit a query string parameter by parameter?

Yes. The Query string table tab parses any URL into rows you can edit, encode or decode individually, sort, dedupe, and rebuild into a URL.

URL Encode / Decode

Encode text for safe use in URLs or decode percent-encoded strings back to readable characters. Choose between encodeURIComponent, encodeURI, application/x-www-form-urlencoded (space as +) and strict RFC 3986 (which also encodes ! ' ( ) *). Decoding unwraps every layer of double-encoding and reports how many it found, with precise positions for malformed escapes. The Query string table tab parses any URL into editable key/value rows with per-field encode/decode, sort, dedupe and rebuild. Handles UTF-8 correctly and warns about non-ASCII or punycode hostnames.

Runs locally in your browser

Paste long URLs or many lines — open fullscreen for room

Plain text

0 chars · 1 line

Encoded (encodeURIComponent)

Output will appear here…

Variant

Encodes every reserved character (/ ? # & = +) — the right choice for a single query value or path segment.

Per-line batch

Base64 Encode / Decode

Encode text, hex or any file to Base64 (and Base32, Base58) and decode back — with data URIs and image preview.

HTML Entity Encode / Decode

Encode text to HTML entities with presets (minimal, attribute-safe, all non-ASCII) and decode all 2,000+ HTML5 named references.

URL Parser & Query Editor

Break any URL into parts, edit query params live, unwrap nested redirect URLs, decode ad macros, build UTMs and follow redirects.

Unicode Escape / Unescape

Convert text to \uXXXX, \u{…}, \x, U+, &#x…;, Python, Go or CSS escapes and back, and inspect every code point for invisible or look-alike characters.

How to use URL Encode / Decode

1Pick Encode or Decode and paste your text or URL — the result appears as you type.
2Choose the variant in Options: encodeURIComponent for a single value, encodeURI for a whole URL, form for POST bodies and browser-style query strings, or RFC 3986 strict for OAuth-style signing.
3When decoding, leave "Decode all layers" on to unwrap double- or triple-encoded input; the stats show how many layers were found.
4Switch to the Query string table to parse a URL into key/value rows, edit or encode/decode individual fields, sort, dedupe, and copy the rebuilt URL.
5Turn on per-line batch to convert a list of values at once; Swap (⌘⇧S) flips direction with the current output.

About URL Encode / Decode

URL Encode / Decode is part of FizzKit — a collection of focused developer and ad-tech tools. Because everything runs locally, it works offline once loaded and never exposes your data to a remote server.

Frequently asked questions

encodeURI preserves characters that give a URL its structure (: / ? # & =), so use it on a complete URL. encodeURIComponent encodes those too, which is what you want for a single query value or path segment.

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