URL Encoder & Decoder

Q: What is the difference between encodeURI and encodeURIComponent?

encodeURI encodes a full URI but preserves characters that have special meaning in a URL (like /, ?, #, &, =). encodeURIComponent encodes everything except letters, digits, and a few safe characters (- _ . ! ~ * ' ( )), making it ideal for encoding individual query parameter values.

Q: When should I use URL encoding?

URL encoding is necessary whenever you include special characters in a URL, such as spaces, ampersands, or non-ASCII characters. Common cases include building query strings, embedding user input in URLs, passing data through redirects, and constructing API request URLs.

Q: Is this URL encoder safe for sensitive data?

Yes. All encoding and decoding happens entirely in your browser using JavaScript. No data is sent to any server, stored, or logged. You can safely encode API keys, tokens, and other sensitive values.

Q: What does the query string parser do?

The query string parser takes a full URL and extracts all query parameters into a table of key-value pairs. Each value is automatically decoded, and you can copy individual values or download the entire set as JSON.

Encode and decode URLs instantly. Choose between encodeURIComponent, encodeURI, or full percent-encoding. Parse query strings, build URLs, and copy results with one click. Free. No sign-up.

Decoded (Raw)

Encoded

Query String Parser

Paste a full URL to extract and decode all query parameters.

How it works

1
Enter your text
Paste or type raw text in the left panel, or an encoded URL in the right panel. The tool auto-detects percent-encoded input on paste.
2
Choose encoding mode
Select encodeURIComponent for query values, encodeURI for full URLs, or Full Encode for every non-alphanumeric character.
3
Copy or build
Copy the encoded or decoded result. Use the Query String Parser to inspect URL parameters, or the URL Builder to construct URLs from parts.

Why URL Encoding Matters for Developers

URLs are the backbone of the web, yet they have strict rules about which characters are allowed. Spaces, ampersands, question marks, non-ASCII characters, and many other symbols must be percent-encoded before they can safely appear in a URL. Without proper encoding, links break, API calls fail, and data gets corrupted during transmission.

JavaScript provides two built-in functions for URL encoding: encodeURI and encodeURIComponent. The difference is subtle but critical. encodeURI is designed for encoding a complete URI, so it preserves characters like /, ?, #, and & that have structural meaning. encodeURIComponent encodes everything except unreserved characters, making it the right choice for encoding individual query parameter values, form data, or any string that will become part of a larger URL.

Common scenarios where URL encoding is essential include building API request URLs with dynamic parameters, constructing OAuth callback URLs, embedding user-generated content in links, passing data through URL redirects, and creating mailto links with pre-filled subjects and bodies. Getting the encoding wrong in any of these cases can lead to security vulnerabilities, broken integrations, or data loss.

The Query String Parser in this tool is particularly useful for debugging. Paste a complex URL with dozens of parameters, and instantly see every key-value pair decoded and organized in a table. This saves time when inspecting tracking URLs, debugging OAuth flows, or reverse-engineering API endpoints. You can copy individual values or download everything as JSON for further analysis.

All processing runs entirely in your browser. Your URLs and data never leave your device, making this tool safe for encoding API keys, tokens, session IDs, and other sensitive information.

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Frequently Asked Questions

What is the difference between encodeURI and encodeURIComponent?+

When should I use URL encoding?+

Is this URL encoder safe for sensitive data?+

What does the query string parser do?+

What is Full Encode mode?+

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