Quick Answer

URL Encoder & Decoder is a free online URL encoder and decoder tool by ThinkaBell. It runs all encoding and decoding happens locally in your browser — no sign-up, no file uploads, and no data ever leaves your device.

Encode & decode: Switch between encoding and decoding mode with a single click
Live preview: See the result update in real-time as you type or toggle options
Component & full URI: Choose between encodeURIComponent and encodeURI for precise control
Privacy-first: no data collection, no tracking, no uploads.
Free forever: no premium tiers, no hidden charges, no accounts.

Free URL Encoder & Decoder

Encode and decode URLs, query parameters, and path segments instantly. Live preview, one-click swap, and full client-side processing.

Working with URLs often means dealing with special characters that break links, corrupt API requests, or cause encoding errors. This tool lets you encode any string into a URL-safe format or decode a percent-encoded string back to its original form — instantly, entirely in your browser. Toggle between full URI and component encoding modes, swap between encode and decode with one click, and preview results live as you type. Nothing is stored, transmitted, or tracked.

Component mode (encodeURIComponent) Encodes everything except A-Z a-z 0-9 - _ . ~

Live Preview

About URL Encoder & Decoder

URL Encoder & Decoder is a free web-based URL encoding and decoding tool by ThinkaBell that runs 100% locally in your browser. No sign-up, no server uploads, no tracking — every encoding and decoding operation happens on your device using the browser's built-in URI functions. This makes it safe for API keys, authentication tokens, personal data, and any other sensitive URL content.

URL encoding (also known as percent-encoding) is the standard mechanism for representing characters that are not allowed or have special meaning in URLs. When you include a space, an ampersand, an equals sign, or any non-ASCII character in a URL, it must be encoded to ensure the URL is transmitted and parsed correctly. The encoding replaces each reserved or unsafe character with a percent sign (%) followed by two hexadecimal digits representing the character's ASCII or UTF-8 byte value. For example, a space becomes %20, an exclamation mark becomes %21, and a Chinese character like "你好" becomes %E4%BD%A0%E5%A5%BD.

This tool provides two encoding modes to match your specific needs. The default Component mode uses encodeURIComponent(), which encodes everything except unreserved characters (A-Z, a-z, 0-9, -, _, ., ~). This is the correct choice when encoding individual query parameter values, form field values, or any string that will be inserted into a URL structure. The Full URI mode uses encodeURI(), which preserves URL-structural characters like :, /, ?, #, &, and =. Use this when you have a complete URL and need to encode only the unsafe characters while keeping the URL structure intact.

The live preview updates as you type, so you can see the encoding or decoding result in real-time without clicking any buttons. The Swap button lets you instantly move the result to the input field for further processing — useful when you need to double-encode or double-decode. Copy puts the result on your clipboard, and Clear resets everything. The entire workflow is designed for speed: paste, encode or decode, copy, and move on.

Instant encoding and decoding with no processing delay
Component mode (encodeURIComponent) for query values
Full URI mode (encodeURI) for complete URLs
Live preview updates as you type
One-click swap between input and output
Copy result to clipboard with fallback support
Keyboard shortcuts for power users
Zero data collection — no cookies, no analytics, no server calls

Why This URL Encoder & Decoder

Uses native browser encoding functions for accuracy
Two modes for different use cases
Live preview — no need to click to see results
Swap button for quick round-trip encoding
Works offline once the page loads
Mobile-friendly with large tap targets
Handles Unicode and international characters
Free forever with no premium tiers or account walls

How to Use the URL Encoder & Decoder

Encode or decode any URL string in seconds. Follow these steps to convert between plain text and URL-safe format.

Choose your mode by clicking Encode or Decode at the top of the form. Encode mode converts plain text into URL-safe percent-encoded strings. Decode mode reverses percent-encoded strings back to their original form.
Select the encoding type using the Component checkbox. When checked, the tool uses encodeURIComponent() — ideal for encoding individual query parameter values, API keys, or form data. Uncheck it to use encodeURI(), which preserves URL-structural characters like :, /, ?, and & for encoding complete URLs.
Paste or type your input into the textarea. Enter a URL, a query string, a special character, or any text you want to encode or decode. The live preview below the textarea shows the result in real-time as you type.
Click Encode (or Decode) to process the input. The result appears in the output area below with the full encoded or decoded string. If you need to process the result further, click Swap to move it to the input field.
Copy the result using the Copy button and paste it wherever you need it — API requests, configuration files, browser address bar, or code. Click Clear to reset the tool and start fresh.

Frequently Asked Questions

What is URL encoding?

URL encoding (also called percent-encoding) is a mechanism for converting characters that are not allowed in a URL into a format that can be transmitted over the Internet. Reserved characters like spaces, question marks, and ampersands are replaced with a percent sign followed by two hexadecimal digits representing the character's ASCII code. For example, a space becomes %20, an exclamation mark becomes %21, and a forward slash becomes %2F. This system is defined in RFC 3986 and is essential for safe URL transmission.

When should I URL encode?

You should URL encode whenever you include special characters in a URL path or query parameter. This includes spaces, non-ASCII characters (like accented letters or Chinese characters), and URL-reserved characters used as literal values (like ?, &, =, #). Common scenarios include building API requests with query strings, constructing search URLs with user input, handling form submissions programmatically, and web scraping where URLs contain special characters that need preservation.

What's the difference between encodeURI and encodeURIComponent?

encodeURI() encodes a complete URI but preserves URL-structural characters like :, /, ?, #, &, and =. It is designed for encoding an entire URL where you want to keep the structure intact. encodeURIComponent() encodes everything except letters, digits, -, _, ., and ~. It is designed for encoding individual URL components like query parameter values, where characters like & and = must be encoded because they have special meaning in the URL structure. When in doubt, use encodeURIComponent — it is the safer default.

Why do spaces become %20?

URLs cannot contain literal spaces because the space character is used as a delimiter in many Internet protocols and would cause parsing errors. The percent-encoding for a space is %20 because the ASCII code for space is 32 in decimal, which converts to 20 in hexadecimal. The percent sign (%) signals that the following two digits represent an encoded character. Some systems use + instead of %20 for spaces in query strings, but %20 is the standard encoding defined in RFC 3986.

Is URL encoding the same as encryption?

No. URL encoding is a reversible character substitution scheme used to represent special characters in URLs — it provides no security or confidentiality. Anyone can decode a URL-encoded string by reversing the percent-encoding. Encryption, on the other hand, uses mathematical algorithms and secret keys to transform data into an unreadable form that can only be decrypted with the correct key. URL encoding is for safe transport, not for protecting data. Never use URL encoding as a security measure.

Key Terms

Percent-Encoding: A mechanism for encoding characters in URLs by replacing them with a % followed by two hexadecimal digits representing the character's byte value.
encodeURIComponent: A JavaScript function that encodes a URI component by encoding all characters except A-Z, a-z, 0-9, -, _, ., and ~. Ideal for encoding query parameter values.
encodeURI: A JavaScript function that encodes a full URI by preserving URL-structural characters like :, /, ?, #, &, and = while encoding unsafe characters.
Query String: The portion of a URL that follows the question mark (?), containing key-value pairs separated by ampersands (&). Values in query strings must be URL-encoded.
URI: Uniform Resource Identifier — a string of characters that unambiguously identifies a particular resource. URLs are the most common type of URI.
RFC 3986: The Internet standard that defines the generic syntax of URIs, including which characters are reserved, unreserved, and how percent-encoding works.