URL Encoder/Decoder

URL encoding — also called percent-encoding — replaces unsafe characters in a URL with a percent sign followed by a two-digit hexadecimal representation of the character's byte value. It is what turns a space into %20, a plus sign into %2B, and a space-plus-sign combination into %20%2B. Anywhere a URL touches text that was not already URL-safe — search queries, user-submitted form fields, webhook callbacks, deep links — you need this encoding in order to carry the data across the wire intact.

The URL RFC (3986) defines two sets of characters: reserved (those with special meaning inside a URL, like :, /, ?, &,=, #) and unreserved (letters, digits, and a handful of punctuation characters). When you encode, you swap any character that is not unreserved for its percent-encoded form. Anything else — whether it's a Cyrillic letter, an emoji, a whitespace character, or just an accented é — needs encoding.

This tool offers two scopes. Component mode usesencodeURIComponent, which encodes every character except unreserved ones. Use this when you're encoding a single value — a query parameter, a path segment, user-supplied content. Full URL mode uses encodeURI, which preserves the URL-structural characters like :/?#&=+. Use this when you have a whole URL and want to escape only the unsafe bits within it, without breaking the scheme, authority, path, or query structure. Mixing them up is the most common URL-encoding mistake: encodeURI("?a=1&b=2") leaves the ? and & untouched, which is fine for URLs but wrong for a single query value.

Decoding reverses the operation. %20 becomes a space; %E2%98%95 decodes to ☕ (under UTF-8, which is the modern web default). Malformed input — a stray % without two hex digits after, or a sequence that is not valid UTF-8 — throws; the tool shows a friendly error when that happens. If your input was URL-encoded under a non-UTF-8 encoding (old CP-1252 data, for example), you'll need a byte-level converter rather than this browser-level one.

Plus-sign ambiguity is a classic trap. In query strings, the plus character (+) is sometimes used to represent a space (a legacy of application/x-www-form-urlencoded, the HTML form encoding), but in URL paths a plus is just a plus. decodeURIComponent does not convert plus to space. If you're decoding query strings you got from an HTML form, replace + with space first. Our decoder leaves plus alone; you can always paste the result back through a search-and-replace.

1. Pick encode or decode. Tabs at the top flip the direction.
2. Choose a scope. Component for single values; Full URL for a complete URL string.
3. Paste your input. Any length, any Unicode.
4. Copy the result. Ready to paste into an address bar, curl command, or API call.
5. Swap and verify. Click swap to feed the output back in and round-trip — a clean encode/decode should give you the exact original.

• Encode and decode in one tool with a quick mode swap.
• Component vs. Full URL scope to match your exact use case.
• Graceful error on malformed input rather than a silent failure.
• Unicode-safe (UTF-8) for emoji and non-Latin scripts.
• Runs entirely in your browser — no data uploaded.