Encode or decode URLs and query strings instantly, with automatic parsing of paths, parameters, and percent-encoded special characters.
Parameter keys and values parsed sequentially without reordering.
| Key | Decoded Value | Encoded Value | Action |
|---|
No query string parameters detected. Enter a URL or query string (e.g. key=val&foo=bar) above.
Quick reference table showing percent hexadecimal codes and URI structural roles.
| Char | Status | Percent Code | Usage / Description |
|---|---|---|---|
| Space | Reserved | %20 or + | Whitespace delimiter |
| & | Reserved | %26 | Query parameter separator |
| = | Reserved | %3D | Key-value assignment |
| ? | Reserved | %3F | Query string initiator |
| # | Reserved | %23 | Fragment / anchor identifier |
| % | Reserved | %25 | Percent-encoding prefix indicator |
| + | Reserved | %2B | Literal plus or form space |
| / | Reserved | %2F | Path segment delimiter |
| : | Reserved | %3A | Scheme/port delimiter |
| ; | Reserved | %3B | Matrix parameter delimiter |
| @ | Reserved | %40 | Userinfo authority delimiter |
| A-Z a-z 0-9 | Unreserved | Unchanged | Standard alphanumeric characters |
| - _ . ~ | Unreserved | Unchanged | RFC 3986 unreserved symbols |
Access recent encoded or decoded URL records saved locally in your session.
Internet protocols transmit URLs using the US-ASCII character set. Non-ASCII characters (such as emojis or foreign scripts) and reserved structural symbols (like spaces, ampersands, or question marks) must be percent-encoded into hexadecimal byte triplets (%XX) to prevent protocol errors.
encodeURI() is designed for complete URLs and preserves structural delimiters like slashes (/), question marks (?), colons (:), and ampersands (&). encodeURIComponent() is intended for query parameter values or path segments, encoding all reserved delimiters to prevent interfering with host URL parsing.
HTML forms submitted with the application/x-www-form-urlencoded format convert spaces into plus symbols (+) instead of %20. Our tool lets you toggle handling of + as literal spaces during query parameter decoding.
Standard JavaScript encodeURIComponent leaves sub-delimiters !'()* unescaped. Strict RFC 3986 mode additionally escapes these symbols (%21, %27, %28, %29, %2A) for strict API payload compatibility.
Percent-encoding only formats characters for transport over HTTP/HTTPS protocols; it does not encrypt or protect data. Anyone can decode URL percent-encoded strings back to plain text.
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Quick answers about how this tool works.
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