URL Encoder & Decoder - Free Online Tool

Encode or decode URLs and special characters for web use. Instant results, browser-based. Essential tool for web developers.

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URL encoding and decoding explained

URLs can only contain certain characters. Special characters like spaces, ampersands, and non-ASCII characters need to be percent-encoded. This tool encodes text for safe use in URLs or decodes URL-encoded strings back to readable text.

URL encoding (percent-encoding) replaces each unsafe character with a percent sign followed by its two-digit hexadecimal ASCII value. Spaces become %20, ampersands become %26, equals signs become %3D, and non-ASCII characters like accented letters are encoded as multi-byte UTF-8 sequences. This ensures URLs conform to RFC 3986 and can be transmitted through any system.

URL encoding is necessary when constructing query parameters with user input, sharing URLs that contain special characters or non-Latin scripts, building API requests with dynamic values, creating mailto: links with pre-filled subject lines, and encoding file paths that contain spaces or special characters for web servers.

Encode only the values in query parameters, not the entire URL - encoding the ? and & delimiters would break the URL structure. Use encodeURIComponent() rather than encodeURI() when encoding individual parameters, as the latter preserves characters like & and = that have special meaning in URLs. When debugging encoded URLs, decode them first to read the actual values being sent.

Browser developer tools show encoded URLs in the Network tab, and most programming languages offer built-in encoding functions. Online decoders like urldecoder.org provide similar functionality. This tool handles both encoding and decoding with instant results, making it faster than looking up function names or opening developer tools for a quick URL debugging session.

How the URL Encoder Works

01Paste or type the text you want to encode or decode
02Choose Encode to convert special characters to URL-safe format, or Decode to convert back
03The result updates instantly
04Copy the encoded or decoded URL to your clipboard

Why URL Encoding Matters

URL encoding (percent-encoding) replaces unsafe characters with a % followed by their hex code. Spaces become %20, ampersands become %26, and so on. This is necessary because URLs can only contain a limited set of ASCII characters. When building URLs with query parameters, always encode user input to prevent broken links and security vulnerabilities like injection attacks.

When to Use URL Encoding

Use URL encoding whenever you construct URLs with user input, share URLs containing special characters or non-Latin scripts, build API requests with dynamic query parameters, create mailto: links with pre-filled subject lines or body text, or debug encoded URLs received from external systems.

Common Use Cases

Encode query parameter values containing special characters for API requests Base64 Encoder & Decoder - Free Online
Decode URL-encoded strings in API responses or server logs for debugging
Encode non-Latin characters (accented letters, CJK) for use in URLs
Create properly encoded mailto: links with pre-filled subjects and body text
Debug double-encoded URLs where %20 has become %2520 JSON Formatter & Validator - Instant Results

Expert Tips

Encode only the values in query parameters, not the entire URL - encoding the ? and & delimiters would break the URL structure
Watch for double-encoding: if you see %2520 instead of %20, your URL was encoded twice - decode once to fix it
Use encodeURIComponent() (not encodeURI()) when encoding individual parameter values in JavaScript - encodeURI preserves characters like & that have special meaning in URLs

Frequently Asked Questions

What is URL encoding?→

URL encoding (percent-encoding) replaces characters that are not allowed in URLs with a percent sign followed by their hexadecimal ASCII code. For example, a space becomes %20, an ampersand becomes %26. This ensures the URL is valid and transmitted correctly.

Which characters need encoding?→

Spaces, ampersands (&), equals signs (=), question marks (?), hash signs (#), and all non-ASCII characters (accented letters, CJK characters, emoji) need encoding when used in URL query values. Reserved characters like / and : only need encoding when used outside their intended purpose.

What is the difference between encodeURI and encodeURIComponent?→

encodeURI() encodes a full URL but preserves structural characters like :, /, ?, and &. encodeURIComponent() encodes everything except letters, digits, and a few safe characters. Use encodeURIComponent() for individual query parameter values.

Is this tool free and private?→

Yes. All encoding and decoding happens in your browser - no data is sent to any server. Your URLs and text remain completely private.

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