URL Encoder/Decoder

URL encoding, also called percent-encoding, converts characters that are not allowed in URLs into a safe format using a percent sign followed by two hexadecimal digits. For example, a space becomes %20 and an ampersand becomes %26. This is necessary because URLs can only contain a limited set of ASCII characters. Without encoding, special characters like spaces, question marks, and hash symbols would break the URL structure. Browsers handle this automatically when you click links, but developers often need to encode strings manually when building API requests or constructing query parameters in code.

This tool offers two encoding modes that correspond to JavaScript's built-in functions. encodeURIComponent is the more aggressive option and encodes almost everything except letters, digits, hyphens, underscores, periods, and tildes. Use it when encoding individual query parameter values. encodeURI is designed for encoding a complete URL and preserves structural characters like colons, slashes, question marks, and hash symbols. Choosing the wrong mode is a common source of bugs. As a rule of thumb, use URI Component mode for parameter values and Full URI mode for complete URLs.

URL encoding is essential whenever you pass user-generated content as part of a URL. This includes search queries, form submissions sent via GET requests, redirect URLs embedded as parameters, and any text that might contain international characters or special symbols. API developers frequently need to encode parameters when constructing request URLs by hand. If you are debugging a URL that is not working correctly, try decoding it with this tool to see the original values and check whether the encoding was applied correctly. For encoding binary data in text-safe formats, our Base64 Encoder/Decoder is a great companion. You might also find our JSON Formatter helpful when working with API payloads that contain encoded URLs.