URL Encoder/Decoder
Encodes for use as a URL parameter value. Encodes all special characters including /, ?, &, =.
About the URL Encoder/Decoder
The URL Encoder/Decoder applies and reverses percent-encoding, the mechanism that lets URLs carry characters that would otherwise be reserved, unsafe, or non-ASCII. Encoding replaces each problematic byte with a percent sign followed by its two-digit hexadecimal value, so a space becomes %20 and an ampersand becomes %26. This keeps query strings, path segments, and fragments from breaking when they contain spaces, slashes, question marks, or Unicode characters.
Under the hood, URL encoding follows RFC 3986, which defines which characters are reserved (like : / ? # [ ] @ & = + and ,) and which are unreserved and safe to leave alone. Different parts of a URL have different rules: a value inside a query string must encode characters that are perfectly legal inside a path. This tool handles the conversion in both directions so you can prepare a value for safe insertion or read an already-encoded string back into plain text.
Typical use cases include building query parameters by hand, debugging redirect URLs, decoding tracking links full of %-sequences, and preparing search terms or filenames that contain spaces and special characters. Developers also reach for it when an API rejects a request because a parameter was double-encoded or left raw.
A useful tip: distinguish between encodeURIComponent-style encoding, which escapes nearly everything including & and =, and encodeURI-style encoding, which preserves the URL structure. Use full-component encoding for individual parameter values and structural encoding for whole URLs. When you need to break a link into pieces, the URL Parser complements this tool, and for binary payloads in URLs consider the Base64 Encoder/Decoder.
Frequently asked questions
- Why is a space turned into %20 sometimes and a plus sign other times?
- Percent-encoding always uses %20 for a space. The plus sign represents a space only in the older application/x-www-form-urlencoded form data format, not in general URLs.
- When should I encode the whole URL versus just one parameter?
- Encode individual parameter values fully so characters like & and = are escaped. Encode a whole URL only structurally so the slashes and the scheme stay intact.
- What causes double-encoding problems?
- Double-encoding happens when an already-encoded string is encoded again, turning %20 into %2520. Decode once to check, and encode a value only at the final assembly step.
- Does this tool handle non-English characters?
- Yes. Unicode characters are first converted to UTF-8 bytes, then each byte is percent-encoded, which is how URLs carry accented letters, emoji, and other scripts.