What is percent-encoding?

Percent-encoding is the official term for URL encoding defined in RFC 3986. It converts characters to %XX format where XX is the hexadecimal representation of the character's byte value in UTF-8.

Why is it called percent-encoding?

It's called percent-encoding because encoded characters are represented with a percent sign (%) followed by hexadecimal digits. For example, a space becomes %20.

RFC 3986 is the internet standard that defines URI (Uniform Resource Identifier) syntax, including the percent-encoding mechanism. It specifies which characters are allowed in URIs and how to encode others.

Which characters need percent-encoding?

Characters outside the unreserved set (A-Z, a-z, 0-9, -, ., _, ~) should be percent-encoded. This includes spaces, most punctuation, and all non-ASCII characters. Reserved characters (:, /, ?, #, [, ], @, !, $, &, ', (, ), *, +, ,, ;, =) are encoded when used outside their reserved purpose.

Is percent-encoding the same as URL encoding?

Yes, percent-encoding and URL encoding are the same thing. Percent-encoding is the formal technical term, while URL encoding is the common name developers use.

When should I use percent-encoding?

Use percent-encoding whenever you include user data, special characters, or non-ASCII text in URLs, query parameters, form data, or API requests. It ensures data is transmitted safely without breaking URL syntax.

Does percent-encoding work for all languages?

Yes, percent-encoding works for all Unicode characters including Chinese, Arabic, Hebrew, emoji, and other non-ASCII text. Each character is converted to its UTF-8 byte sequence and then percent-encoded.

Is this tool safe for sensitive data?

Yes, this tool runs entirely in your browser. No data is sent to any server, making it safe for encoding sensitive information.

Percent Encode

Percent-encode text and URLs by converting characters to %XX hexadecimal format

Text (Plain)

Input

Mode

Text (Percent-Encoded)

Output

What is Percent Encode?

This Percent Encode tool implements RFC 3986 percent-encoding standard, converting characters into %XX hexadecimal format for use in URLs and URIs. Percent-encoding is the official name for URL encoding—it replaces unsafe characters with a percent sign (%) followed by two hexadecimal digits. This is essential for web development, API integration, and ensuring data can be safely transmitted in URLs without breaking syntax or causing parsing errors.

How to Use

Paste text that needs percent-encoding

Click Encode to convert to %XX format

Copy the percent-encoded output

Use in URLs, query strings, or API requests

Common Use Cases

Encode data for URL query parameters and form submissions

Implement RFC 3986 compliant URL encoding

Encode path segments and query values for REST APIs

Prepare data for OAuth callbacks and redirects

Encode file names and paths for web applications

Create valid URIs with special characters

Key Features

RFC 3986 compliant percent-encoding

Converts characters to %XX hexadecimal format

Handles ASCII and Unicode characters

One-click copy to clipboard

Client-side processing - privacy-friendly

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Quick Examples

Try these to get started

Percent-encode spaces

Convert space to %20

hello world

Encode special characters

Encode symbols to %XX format

value=100%&status=ok

Encode path segment

Encode spaces in URL path

/api/users/John Doe

Encode query string

Encode ampersand and space

search=coffee & tea

Encode Unicode

Encode accented characters

café résumé

Common Questions

Find answers quickly

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Percent Encode

What is Percent Encode?

How to Use

Common Use Cases

Key Features

Related Articles

Base64 Encoding and Decoding: Complete Developer Guide

Quick Examples

Percent-encode spaces

Encode special characters

Encode path segment

Encode query string

Encode Unicode

Common Questions

What is percent-encoding?

What is percent-encoding?

Why is it called percent-encoding?

Why is it called percent-encoding?

What is RFC 3986?

What is RFC 3986?

Which characters need percent-encoding?

Which characters need percent-encoding?

Is percent-encoding the same as URL encoding?

Is percent-encoding the same as URL encoding?

When should I use percent-encoding?

When should I use percent-encoding?

Does percent-encoding work for all languages?

Does percent-encoding work for all languages?

Is this tool safe for sensitive data?

Is this tool safe for sensitive data?

Related Tools

URL Encoder & Decoder

URL Encode

Percent Decode

Query String Encode

Base64 Encoder / Decoder

HTML Escape & Unescape

JSON Escape & Unescape

Percent Encode

What is Percent Encode?

How to Use

Common Use Cases

Key Features

Related Articles

Base64 Encoding and Decoding: Complete Developer Guide

Quick Examples

Percent-encode spaces

Encode special characters

Encode path segment

Encode query string

Encode Unicode

Common Questions

What is percent-encoding?

What is percent-encoding?

Why is it called percent-encoding?

Why is it called percent-encoding?

What is RFC 3986?

What is RFC 3986?

Which characters need percent-encoding?

Which characters need percent-encoding?

Is percent-encoding the same as URL encoding?

Is percent-encoding the same as URL encoding?

When should I use percent-encoding?

When should I use percent-encoding?

Does percent-encoding work for all languages?

Does percent-encoding work for all languages?

Is this tool safe for sensitive data?

Is this tool safe for sensitive data?

Related Tools

URL Encoder & Decoder

URL Encode

Percent Decode

Query String Encode

Base64 Encoder / Decoder

HTML Escape & Unescape

JSON Escape & Unescape