What is percent-encoding in URLs?

Percent-encoding replaces unsafe or reserved ASCII characters with a "%" followed by their two-digit hexadecimal value (e.g., spaces become "%20").

Why must URLs be encoded?

URLs can only contain a specific set of ASCII characters. Special characters like spaces, question marks, and ampersands have reserved meanings that disrupt routing unless encoded.

What is the difference between encoding a full URL and encoding a query parameter?

A full URL preserves structural characters ("http://", "/", "?"), while parameter encoding encodes reserved characters like "&" and "=" so they do not break key-value pairs.

Does this tool decode "+" as a space?

Yes. In URL query string form data, "+" frequently represents spaces and is properly decoded into standard spaces.

Are URLs sent over the network during encoding?

No. All percent-encoding calculations happen client-side in your browser.

Dev Tools

URL Encoder/Decoder

Encode or decode URLs and query parameters.

100% Private & Client-Side Execution

URL strings are parsed locally in browser memory. No links or parameters are logged.

About URL Encoder/Decoder

URL Encoder & Decoder converts characters into their corresponding percent-encoded representations according to RFC 3986, ensuring URLs transmit safely across HTTP networks without breaking query strings or path parameters.

How to Use URL Encoder/Decoder

Type or paste your URL, query string, or text into the input field.
Click "Encode URL" to convert spaces, ampersands, and special characters into percent-encoded entities (%20, %26, etc.).
Click "Decode URL" to translate a percent-encoded string back into readable characters.
Review the live character counter and converted output.
Click Copy to save the URL to your clipboard.

Common Real-World Use Cases

Web Developers: Safely encode dynamic query parameters, callback URLs, and OAuth redirect URIs.
Digital Marketers: Format UTM tracking parameters and campaign URLs so analytics platforms capture campaign data correctly.
API Engineers: Encode REST API parameters containing spaces, slashes, or non-Latin characters.
Security Testers: Audit web endpoints for parameter pollution and verify proper URL sanitization.

Technical Specifications & Limitations

Implements RFC 3986 percent-encoding standards (such as `encodeURIComponent()` and `decodeURIComponent()`).

Frequently Asked Questions

What is percent-encoding in URLs?: Percent-encoding replaces unsafe or reserved ASCII characters with a "%" followed by their two-digit hexadecimal value (e.g., spaces become "%20").
Why must URLs be encoded?: URLs can only contain a specific set of ASCII characters. Special characters like spaces, question marks, and ampersands have reserved meanings that disrupt routing unless encoded.
What is the difference between encoding a full URL and encoding a query parameter?: A full URL preserves structural characters ("http://", "/", "?"), while parameter encoding encodes reserved characters like "&" and "=" so they do not break key-value pairs.
Does this tool decode "+" as a space?: Yes. In URL query string form data, "+" frequently represents spaces and is properly decoded into standard spaces.
Are URLs sent over the network during encoding?: No. All percent-encoding calculations happen client-side in your browser.

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