URL Encoder Decoder

The difference is how much they encode. encodeURIComponent escapes every reserved character, including : / ? # @ & = + $, so it is meant for a single piece of a URL — typically one query-string value. If that value contained a stray & or =, encoding it prevents the value from accidentally starting a new parameter. encodeURI is gentler: it preserves the structural characters : / ? # so an already-assembled, complete address stays usable as a URL. The rule of thumb is to use encodeURIComponent on the small fragment you are slotting into a URL, and encodeURI on a whole URL you do not want to break apart. Using the wrong one is the single most common URL bug. This tool exposes both as separate scopes, plus path-only and query-only modes, so you can apply exactly the right level.

URLs can only safely carry a limited set of characters, and some characters are reserved because they have a structural meaning. A space is not allowed at all and must become %20, otherwise browsers, servers, and link parsers may truncate the address at the gap. An ampersand is worse: inside a query string & separates one parameter from the next, so an unencoded & sitting inside a value gets read as the start of a brand-new parameter, splitting your data. Encoding it to %26 keeps it as literal text. The same applies to #, which marks a fragment, and ? and / which mark the query and path. Percent-encoding replaces each of these with a safe %-prefixed code. Paste your link into the tool, choose the right scope, and it escapes the unsafe characters for you so the URL holds together.

Both can represent a space, but they belong to different encoding schemes and are not always interchangeable. %20 is the standard percent-encoding for a space and is valid anywhere in a URL — the path, the query, or a fragment. The plus sign only means a space in one specific context: application/x-www-form-urlencoded data, which is how an HTML form submits values. In that format a literal space becomes +, and a literal + must itself be encoded as %2B to avoid being misread as a space. Outside form encoding, a + in a URL is just a plus sign and is not decoded to a space. Mixing the two is a frequent source of bugs where a name like "John Doe" arrives as "John+Doe". This tool offers a dedicated form URL-encoded mode alongside standard percent-encoding so you can pick the convention your endpoint expects.

%2520 is the tell-tale signature of double encoding — a string that was percent-encoded twice. A space first becomes %20; if that result is then encoded again, the % itself gets escaped to %25, turning %20 into %2520. You will often see clusters of stray 25 sequences scattered through a mangled link, like %253A or %252F. It usually happens when code encodes a value that was already encoded, for example wrapping an entire pre-built URL in encodeURIComponent. The fix is simply to decode the string twice: decoding once converts %2520 back to %20, and decoding again recovers the original space. This tool's validator flags double encoding when it detects the pattern, and you can run the decode operation repeatedly to peel back each layer until the URL looks normal again. Paste the suspicious link to confirm and recover the original.

Hostnames follow different rules from the rest of a URL: the host cannot contain non-ASCII letters directly, and it does not use percent-encoding the way a path or query does. Instead, internationalized domain names are converted to Punycode, an ASCII-compatible encoding that prefixes the converted label with xn--. For example, münchen.de becomes xn--mnchen-3ya.de, which is the form that actually travels through DNS, while browsers display the friendly Unicode version to users. The conversion is reversible, so you can turn a Punycode host back into its readable form to verify what a link really points to — useful when checking for look-alike or spoofed domains. This tool's IDN converter handles both directions using the browser's native URL normalization, keeping the host separate from the percent-encoding you would apply to the path and query. Paste a domain to convert it to or from Punycode.