Encode and decode URL components online for free. Handles special characters, percent encoding, query strings, and full URLs — instant results with no server required.
URL Encoder / Decoder is a free online tool that converts text into a URL-safe format (percent-encoding) and decodes percent-encoded strings back to their original form. URLs can only contain a limited set of ASCII characters; special characters like spaces, ampersands, question marks, and non-Latin characters must be percent-encoded to be transmitted correctly. This tool supports both component encoding (encodeURIComponent) and full URL encoding (encodeURI), along with URL parsing and double decoding for multi-layered encoded strings.
Use the URL Encoder whenever you need to safely include special characters in query strings, path segments, or fragment identifiers. It's particularly helpful when building API request URLs with dynamic parameters, debugging encoded URLs from server logs or analytics platforms, or preparing deep links that contain non-ASCII characters. The URL parser breaks any URL into its components (protocol, host, path, query parameters) for easy inspection.
Web developers and API engineers commonly use URL Encoder to construct safe query parameters for REST API calls, decode tracking URLs from marketing campaigns and analytics tools, encode user-generated content before appending it to URLs, debug routing issues caused by improperly encoded characters, and prepare redirect URLs for OAuth flows. The double decode feature handles multi-layered encoding often found in redirect chains and analytics tracking URLs.
Essential terms and definitions related to URL Encoder / Decoder.
A mechanism for encoding special characters in URLs by replacing them with a % sign followed by two hexadecimal digits representing the character's ASCII or UTF-8 byte value. For example, a space becomes %20 and an ampersand becomes %26. This ensures that reserved URL characters are transmitted literally rather than being interpreted as URL structure.
The part of a URL that follows the ? character and contains key-value pairs separated by & symbols (e.g., ?name=John&age=30). Query strings pass parameters to the server. Values containing special characters must be percent-encoded to avoid breaking the URL structure.
Characters that have special meaning in URL syntax: : / ? # [ ] @ ! $ & ' ( ) * + , ; =. These characters delimit URL components (protocol, host, path, query). When these characters appear as literal data within a URL component, they must be percent-encoded to prevent misinterpretation by parsers and servers.
encodeURI encodes a full URI but preserves characters like :, /, and ? that have special meaning in URLs. encodeURIComponent encodes everything except letters, digits, and a few safe characters. This tool uses encodeURIComponent, which is the correct choice for encoding query parameter values.
Yes. The encoder converts non-ASCII characters to their UTF-8 byte sequences and then percent-encodes each byte. This is the standard way to include international characters in URLs.
You can paste an entire URL, but keep in mind that encoding the whole string will also encode the protocol (://) and path separators (/). For best results, encode only the query parameter values individually.
Common errors developers encounter and how to resolve them.
URIError: URI malformed — Percent-encoding decode failure This error occurs when the string being decoded contains invalid percent-encoding sequences (not in %XX format or corrupted UTF-8 byte sequences). For example, incomplete multi-byte UTF-8 sequences like %E2%80 are rejected by decodeURIComponent(). If your input contains a standalone % character, it has not been encoded and must first be encoded as %25. Paste your URL into this tool to identify which segment is malformed.
Double encoding issue: Strange sequences like %2520 If you see %2520 instead of %20 (space) in a URL, the encode function was applied twice to an already-encoded string. The % character gets re-encoded as %25, turning %20 into %2520. Solution: call the encode function only once on the raw string. To check whether data is already encoded, try decoding it first — if the result differs, encoding has already been applied.
Space encoding difference in query strings: + (plus) vs %20 In URL query strings, the space character can be represented in two ways: + (application/x-www-form-urlencoded format) or %20 (RFC 3986 percent-encoding). PHP's urlencode() produces +, while JavaScript's encodeURIComponent() produces %20. If your backend does not interpret the + character as a space, spaces in form data may be lost. Check which format your API expects and use a consistent encoding strategy.