Data Tools

URL Encode and Decode Online Free

πŸ“… April 8, 2026⏱ 6 min read✍️ TaskToolsAI

URLs can only contain a limited set of characters. When you need to include spaces, special symbols, or non-ASCII text in a URL, those characters must be percent-encoded. This guide explains URL encoding and shows you how to encode or decode any string online in seconds.

In this article

  1. What is URL encoding?
  2. How percent encoding works
  3. When to encode vs decode
  4. Common URL encoding examples
  5. URL encoding in query strings
  6. How to encode or decode a URL online

What Is URL Encoding?

URL encoding (also called percent-encoding) is a mechanism for converting characters that are not safe to use in a URL into a format that can be transmitted safely over the internet. The URL specification (RFC 3986) defines a limited set of characters as "unreserved" β€” letters A–Z, digits 0–9, and the symbols -, _, ., and ~. Every other character must be percent-encoded before it can appear in a URL.

You've seen percent-encoding in action without knowing it. The %20 in a URL stands for a space character. The %40 stands for the @ symbol. When you paste a URL into a browser and press Enter, the browser decodes these sequences back into the original characters for display β€” but the encoded form is what travels across the network.

How Percent Encoding Works

The mechanism is straightforward: take the character, find its UTF-8 byte value(s), write each byte as a two-digit uppercase hexadecimal number prefixed with a percent sign.

For single-byte ASCII characters:

  • Space (ASCII 32) β†’ %20
  • Exclamation mark ! (ASCII 33) β†’ %21
  • Hash # (ASCII 35) β†’ %23
  • Ampersand & (ASCII 38) β†’ %26
  • Plus + (ASCII 43) β†’ %2B
  • Equals = (ASCII 61) β†’ %3D
  • Question mark ? (ASCII 63) β†’ %3F
  • At sign @ (ASCII 64) β†’ %40

For multi-byte UTF-8 characters (non-ASCII, like accented letters or emoji), each byte in the UTF-8 sequence gets its own percent prefix. The letter Γ© (UTF-8: 0xC3 0xA9) becomes %C3%A9. The euro sign € (UTF-8: 0xE2 0x82 0xAC) becomes %E2%82%AC.

When to Encode vs Decode

Encode when: you're building a URL that contains user-supplied input, special characters, or non-English text. This includes: constructing API request URLs with query parameters, embedding search terms in URLs, generating share links with dynamic content, or creating redirect URLs in code.

Decode when: you receive a percent-encoded URL and need to read it as a human, debug an API request, check what a redirect target actually says, or extract readable text from a logged URL. Analytics dashboards and server logs often show percent-encoded URLs β€” decoding them makes the data understandable.

Note: never double-encode a URL. If a string is already percent-encoded, encoding it again will turn the % signs into %25, producing malformed results. Always decode first if you're unsure of the input state.

Common URL Encoding Examples

Here are the most frequently encoded characters and their encoded equivalents:

  • Space β†’ %20 (or + in form data/query strings)
  • & β†’ %26 (critical in query strings β€” raw & is a parameter separator)
  • = β†’ %3D (the key=value separator in query strings)
  • + β†’ %2B (+ has a special meaning as "space" in form encoding)
  • / β†’ %2F (slashes separate URL path segments)
  • ? β†’ %3F (the query string delimiter)
  • # β†’ %23 (the fragment identifier)
  • @ β†’ %40 (used in mailto: URLs and older URL auth syntax)
  • " β†’ %22 (quotes must be encoded in HTML href attributes)

URL Encoding in Query Strings

Query strings (the part of a URL after the ?) are the most common context for URL encoding errors. A query string like ?q=hello world&lang=en is invalid because the space and literal & need encoding. The correct form is ?q=hello%20world&lang=en.

There's also a subtle distinction between encodeURIComponent and encodeURI in JavaScript:

  • encodeURI encodes a full URL β€” it leaves characters like /, ?, #, and & intact because they're structural parts of the URL.
  • encodeURIComponent encodes a URL component (like a query parameter value) β€” it encodes /, ?, #, and & because those characters should not be interpreted as URL structure inside a parameter value.

For most practical tasks (encoding a search query or a parameter value), encodeURIComponent behavior is what you want. Online URL encoders default to this behavior.

How to Encode or Decode a URL Online

A browser-based URL encoder/decoder converts any string instantly:

  • To encode: paste your raw text (containing spaces, special characters, or non-ASCII) into the input, select Encode, and get the percent-encoded output.
  • To decode: paste a percent-encoded URL or string, select Decode, and read the human-readable result.

Combine URL encoding with other data tools for common workflows: format JSON with the JSON formatter before encoding it as a query parameter, or use the extra spaces remover to clean up strings before encoding them into URLs.

Frequently Asked Questions

What is the difference between %20 and + for spaces? +
Both represent spaces, but in different contexts. %20 is the correct percent-encoding of a space in URL paths and most URL components. The + sign means space only in the application/x-www-form-urlencoded format (HTML form submissions and query strings). In a URL path, a literal + means a plus sign, not a space. When in doubt, use %20.
Do I need to encode the entire URL or just parts of it? +
Only encode the parts that contain special characters β€” typically query parameter values and path segments with user-supplied data. The structural parts of a URL (scheme, host, path separators, query delimiters) should not be encoded. Encoding the entire URL including its structure will break it.
Why does my URL have %25 in it? +
%25 is the percent-encoded representation of the % character itself. If you see %25 where you expect %20 or another code, you likely double-encoded the string β€” encoded something that was already encoded. Decode once to recover the intended single-encoded form.
How do I encode a URL in JavaScript? +
Use encodeURIComponent() for encoding individual parameter values: encodeURIComponent("hello world") returns "hello%20world". Use encodeURI() only for encoding a full URL string while preserving URL structure. Never use the deprecated escape() function β€” it doesn't handle Unicode correctly.
Can I decode a URL that contains non-English characters? +
Yes. Non-ASCII characters like Γ©, ΓΌ, δΈ­, or emoji are encoded as multiple %XX sequences representing their UTF-8 bytes. A proper URL decoder reads these byte sequences and converts them back to the correct Unicode characters. For example, %C3%A9 decodes to Γ©.

Related Free Tools

πŸ“‹JSON Formatter πŸ”„CSV ↔ JSON βœ‚οΈRemove Extra Spaces πŸ”€Case Converter

Related Articles

Data ToolsJSON to CSV Converter Online Free Data ToolsBase64 Encode and Decode Online Free