Common URL Encoding Reference
| Character | Encoded | encodeURI | encodeURIComponent | Description |
|---|
What Is URL Encoding & When Do You Need It?
URL encoding (also known as percent-encoding) is the process of converting special characters in a URL into a format that can be safely transmitted over the internet. When a URL contains characters like spaces, ampersands, or non-ASCII characters, they must be encoded to prevent misinterpretation by browsers and servers.
For example, a space character becomes %20, an ampersand becomes %26, and a hash becomes %23. Our tool supports two encoding modes — encodeURI for full URLs (preserves ://?=&) and encodeURIComponent for individual query parameter values (encodes everything including ://?=&).
Everything You Need in a URL Encoder Tool
A fast, accurate, developer-grade URL encoding tool with zero friction.
Real-Time Processing
Results update as you type. No button needed — encoding and decoding happens instantly with every keystroke.
Two Encoding Modes
Switch between encodeURIComponent (for query params) and encodeURI (for full URLs) to get exactly the right output every time.
Swap Input & Output
Click the swap button to instantly move the output back to the input field — perfect for quick encode → decode round-trips.
Character Stats
See input length, output length, total character difference, and number of encoded characters at a glance.
Reference Table
Built-in encoding reference table shows how common characters are encoded in both encodeURI and encodeURIComponent modes.
100% Private
All processing happens in your browser using native JavaScript. Your URLs and data are never sent to any server.
Frequently Asked Questions
Everything you need to know about URL encoding and our tool.
URL encoding (percent-encoding) converts special characters in a URL into a % followed by their hexadecimal ASCII value. For example, a space becomes %20, & becomes %26. This ensures URLs are safely transmitted over the internet without misinterpretation.
encodeURI encodes a complete URL and preserves characters valid in URLs like ://?=&. encodeURIComponent encodes a URL component and converts all special characters including ://?=&. Use encodeURIComponent for individual query parameter values, and encodeURI for full URLs.
URL encode data when passing values in query strings, building API requests, handling GET form submissions, or including user-generated text in URLs. Special characters can break URL structure and cause server errors if not encoded.
Yes, 100% free. No account, sign-up, or payment required. Encode and decode unlimited URLs at no cost, forever.
No. All encoding and decoding happens in your browser using JavaScript's built-in encodeURI and encodeURIComponent functions. Your data never leaves your device.
Characters that get encoded include: space (%20), # (%23), & (%26), + (%2B), = (%3D), ? (%3F), / (%2F), : (%3A), @ (%40), and all non-ASCII characters. The exact set depends on whether you use encodeURI or encodeURIComponent.
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