Input URL
Encoded Output
URL Encoder/Decoder
Encode and decode URLs with percent encoding instantly
What This Tool Does
This URL encoder converts special characters in URLs to percent-encoded format, making them safe for transmission over the internet. The decoder reverses this process, converting percent-encoded URLs back to readable text.
All encoding and decoding happens in your browser. When you paste a URL or text, it processes the data locally without sending anything to a server.
Who Needs This
Web developers building applications that generate URLs with query parameters use this tool to encode user input safely. Special characters like spaces, ampersands, and equals signs must be encoded to prevent breaking URL structure.
API developers who construct URLs programmatically need to encode parameters correctly. An unencoded ampersand in a parameter value can break query string parsing.
Digital marketers creating tracking URLs with UTM parameters use encoding to ensure campaign names and sources containing spaces or special characters work correctly across all platforms.
Key Features
URL Encoding
Converts special characters to percent-encoded format using %XX notation where XX is the hexadecimal value of the character.
URL Decoding
Converts percent-encoded URLs back to readable text, replacing %XX sequences with their corresponding characters.
Query String Support
Handles complete URLs including query strings, correctly encoding or decoding parameter names and values.
Two-Way Conversion
Switch between encode and decode modes with one click. The interface updates to show relevant labels for each operation.
Instant Processing
Converts URLs immediately with a single button click. Copy results to clipboard or download as text files.
Client-Side Processing
All operations run in your browser. URLs and text stay on your device throughout the encoding and decoding process.
When URL Encoding is Required
URLs can only contain certain characters from the ASCII character set. Other characters must be percent-encoded:
Spaces: The most common case. Spaces in URLs must be encoded as %20 or as plus signs (+) in query strings. For example, "hello world" becomes "hello%20world".
Reserved Characters: Characters like ampersand (&), equals (=), question mark (?), and hash (#) have special meaning in URLs. When these appear in parameter values, they must be encoded to prevent misinterpretation.
Non-ASCII Characters: Accented letters, emoji, and characters from non-Latin alphabets must be encoded. For example, "café" becomes "caf%C3%A9".
Special Symbols: Characters like quotes, angle brackets, and percent signs themselves need encoding when used in URLs.
Encoding vs Components
This tool uses encodeURIComponent, which encodes everything except letters, numbers, and the characters: - _ . ! ~ * ' ( )
This is appropriate for encoding individual query string parameters or path segments. It encodes characters like forward slashes and colons, which makes it unsuitable for encoding complete URLs that you want to remain functional.
If you need to encode a complete URL while preserving its structure, only encode the individual parameter values, not the entire URL string.
Common Use Cases
Form Submissions: When HTML forms submit data via GET requests, the browser automatically encodes form fields. This tool helps you verify or manually construct these encoded URLs.
API Requests: REST APIs often accept parameters in the URL. Encoding ensures parameter values don't break the URL structure, especially when values contain ampersands or equals signs.
Sharing URLs: When URLs need to be embedded in other URLs (like redirect parameters), the embedded URL must be encoded to distinguish its parameters from the outer URL's parameters.
Privacy and Security
This tool processes all data in your web browser using JavaScript. When you enter a URL or text, nothing is transmitted to any server. The text is processed locally on your device.
This matters when working with URLs containing authentication tokens, API keys, or sensitive parameters. Since processing is client-side, there's no risk of exposing these values through network transmission.
The tool doesn't save your input to browser storage or cache. When you close the tab, all data is cleared from memory.
Common Questions
Both represent spaces but in different contexts. %20 is the percent-encoded form used anywhere in a URL. The plus sign (+) is specifically for encoding spaces in query string values. This tool uses %20 which works everywhere.
Encode only the parts that need it, typically query parameter values and path segments. Don't encode the protocol (http://), domain name, or structural characters like slashes and question marks that are meant to be part of the URL syntax.
No. All encoding and decoding happens in your browser. The URL stays on your device and is never transmitted anywhere.
This happens when trying to decode text that isn't properly URL-encoded, or when character encoding mismatches occur. Make sure you're decoding actual percent-encoded text that starts with valid %XX sequences.
Characters outside the ASCII alphanumeric set generally need encoding. This includes spaces, most punctuation, non-English characters, and reserved URL characters when they appear in data rather than as URL syntax.
Yes, but be careful. The hash symbol (#) that starts a URL fragment has special meaning. If encoding a complete URL, only encode the parameter values, not the structural characters. If encoding a value that will become a parameter, you can safely encode the entire string including any hash symbols it contains.