URL Encoder Online

Percent-encode strings for safe use in URLs and query parameters — instant browser-based encoding

What Is URL Encoding?

URL encoding (also called percent encoding) converts characters into a format that can be safely transmitted in URLs. Characters that have special meaning in URLs — such as spaces, ampersands, question marks, and equals signs — are replaced with percent-sign followed by their hexadecimal ASCII value. For example, a space becomes %20, an ampersand becomes %26, and a plus sign becomes %2B.

URL encoding is defined by RFC 3986 and is essential for constructing valid URLs that include user input, search queries, form data, API parameters, and any content that might contain characters reserved by the URL syntax. Without proper encoding, special characters in query parameters can break URL parsing, cause security vulnerabilities (injection attacks), or lead to data loss when characters are misinterpreted by servers and browsers.

How to URL Encode a String Online

1. Paste your text or string value into the input field
2. Click Encode to percent-encode all special characters
3. Review the output — spaces become %20, special characters become %XX hex codes
4. Copy the encoded string for use in your URL query parameters, API requests, or form data
5. Use the Decode option to reverse the process and recover the original text

Why Use PinusX for URL Encoding?

PinusX performs URL encoding with 100% client-side processing in your browser. Your strings — which may contain search queries, user data, authentication parameters, or API tokens — never leave your device. Server-based encoding tools process your input on their infrastructure, creating a potential data exposure point. This risk was demonstrated in November 2025, when jsonformatter.org leaked over 80,000 user credentials processed through their servers. PinusX eliminates this vulnerability by running the encoding algorithm locally in your browser tab using JavaScript. No data is transmitted, logged, or stored externally.

Frequently Asked Questions

What is the difference between encodeURI and encodeURIComponent?

encodeURI encodes a full URI but preserves characters that are valid in URLs (like :, /, ?, #, &). encodeURIComponent encodes everything except unreserved characters (letters, digits, -, _, ., ~). Use encodeURIComponent for individual query parameter values, and encodeURI for complete URLs where you want to preserve the structure.

Should spaces be encoded as %20 or +?

Both are used in different contexts. %20 is the standard URL encoding for spaces per RFC 3986. The + sign represents spaces in application/x-www-form-urlencoded format used by HTML forms. Our tool uses %20 by default, which is universally accepted. Some servers also accept + for spaces in query strings.

Do I need to encode Unicode characters?

Yes. Non-ASCII characters like accented letters, emoji, and CJK characters must be UTF-8 encoded first, then each byte is percent-encoded. For example, the character e with an accent becomes %C3%A9. Our tool handles this automatically — paste any Unicode text and it produces correct percent-encoded output.

Which characters are safe in URLs without encoding?

Unreserved characters that never need encoding are: A-Z, a-z, 0-9, hyphen (-), underscore (_), period (.), and tilde (~). All other characters should be encoded when used in URL path segments or query parameter values to ensure the URL is parsed correctly.

Can URL encoding prevent injection attacks?

Proper URL encoding is one layer of defense against URL-based injection attacks. Encoding special characters prevents them from being interpreted as URL structure. However, URL encoding alone is not sufficient security — you also need server-side input validation, parameterized queries, and output encoding appropriate for the context.

Your data never leaves your browser. 100% client-side processing.