Url Encoder

Free online tool. All processing is client-side. No signup needed.

How to Use the Url Encoder

1. Enter your input values above
2. Results update automatically
3. Copy or download the output

What is a Url Encoder?

A URL Encoder (also called percent-encoding) converts special characters in text into a format that can be safely transmitted in a URL. URLs can only contain a limited set of characters from the ASCII character set — letters, digits, and a few special characters (-, _, ., ~). Everything else (spaces, &, ?, #, %, non-ASCII characters like Chinese or emoji) must be percent-encoded: replaced with % followed by the character's hexadecimal byte value. This tool handles both encoding (text → URL-safe) and decoding (percent-encoded → readable text).

How Does It Work?

Paste any text and choose encode or decode. Encoding replaces each unsafe character with %XX where XX is the UTF-8 byte's hex value. For example, space becomes %20, & becomes %26, and 你好 becomes %E4%BD%A0%E5%A5%BD. Decoding reverses this, converting percent-encoded strings back to readable text. The tool handles double-encoding (e.g., %2520 → space) and partial encoding as well.

Formula

Encode:\n• Alphanumeric (A-Z, a-z, 0-9): kept as-is\n• Unreserved (−, _, ., ~): kept as-is\n• Everything else: convert UTF-8 bytes to %XX\n\nCommon encodings:\n• Space → %20 (or + in application/x-www-form-urlencoded)\n• & → %26\n• # → %23\n• ? → %3F\n• % → %25\n• / → %2F (in path, / is allowed; in query, often encoded)\n\nDouble-decode detection: %25XX → decode once to %XX → decode again to character

Who Uses This Tool?

• Web developers constructing URL query parameters with special characters
• SEO specialists encoding non-ASCII characters in URLs
• API developers debugging request URLs with unexpected characters
• Anyone working with Google search URLs, affiliate links, or tracking parameters
• Decoding garbled emails or documents with percent-encoded text

Pro Tips

• Encode query parameter VALUES, not the entire URL. The ?, =, and & between parameters should remain unencoded
• Double-encoding is a common bug: if you see %25 in a URL, it's been encoded twice. Decode once to get the single-encoded version, twice for the original
• For form data (POST requests), browsers use application/x-www-form-urlencoded which encodes spaces as + instead of %20. Know which encoding your server expects
• JavaScript's encodeURIComponent() is the correct function for encoding URL parameter values. encodeURI() is for full URLs and leaves ?, =, & unencoded

Frequently Asked Questions about Url Encoder

Why do I see %20 in URLs?

%20 is the URL-encoded form of a space character. Spaces are not allowed in URLs, so they're replaced with %20 (the ASCII code for space in hexadecimal). In form data, spaces are sometimes encoded as + instead.

Free online Url Encoder — no signup, 100% client-side processing. All data stays in your browser.