URL Encode/Decode
Encode complete URLs or individual values with component, form, or full mode.
Runs in your browser. Nothing is uploaded.
Why URL text needs encoding
URLs have reserved characters with structural meanings. A question mark can begin a query, an ampersand can separate parameters, and a hash can identify a fragment. When one of those characters belongs to a value, percent encoding represents it safely as text. This tool lets you encode a complete value and decode the result in the selected mode.
Paste a URL, a query value, or another piece of URL text. Use the sample to see a space become encoded, then copy or download the result as url.txt. Encoding changes representation only. It does not encrypt data or make a private URL safe to share.
Component mode and form mode
Component mode follows JavaScript URL component behavior. It is a good fit for one path segment, query value, or other component where reserved characters should be escaped as data. It keeps a space as percent-encoded text instead of treating it as a form separator.
Form mode follows the common application/x-www-form-urlencoded convention. Spaces become plus signs during encoding, and decoding treats plus as a space. Choose the mode used by the system receiving the value. A mismatch can produce a valid-looking but different string.
Encode values at the right boundary
Encode a value once at the boundary where it becomes part of a URL. Encoding an entire URL when you meant to encode one query value can escape its separators and change how the browser parses it. Likewise, decoding a complete URL can turn encoded delimiters back into characters with structural meaning. If you are building a query string, handle each parameter according to its server contract.
A malformed percent escape such as %% is not guessed during decode. The page shows an error so you can correct the input. For binary or text representation work, compare the related Base64 tool instead.
Privacy and security boundaries
Input and output remain in your browser. Nothing is uploaded, and there is no account or server-side URL log for the tool. Still, a URL can contain credentials, access tokens, or personal information, so avoid sharing encoded output merely because it looks unfamiliar. Encoding is not a replacement for HTTPS, authorization, or encryption. Hash text locally with Hash Generator when you need a checksum rather than reversible URL representation.
FAQ
Does URL Encode send URLs to a remote service?
Encoding and decoding call JavaScript URL functions in your browser, without a network request. The URL text is never uploaded, and TheDevTab never receives it.
What is Component mode?
Component mode uses encodeURIComponent for one value, such as a query parameter or path segment. Characters that would delimit URL components are percent-encoded so the value does not become URL structure.
What is Form mode?
Form mode starts with component encoding and changes %20 to + for spaces. During decoding it changes every plus sign to a space before applying percent decoding.
What does Full mode preserve?
Full mode uses encodeURI, so it preserves the structure characters expected in a complete URI instead of encoding them as one component. It also restores square brackets after encoding and uses decodeURI in the reverse direction.
Does encoding make a URL secure?
No. Percent encoding changes representation, not permissions, encryption, or authentication. Use HTTPS and application-level security for sensitive data.
What happens for malformed percent escapes?
Decode reports an error when decodeURI or decodeURIComponent rejects malformed percent encoding. It does not silently guess a replacement for an incomplete escape.
What does Decode fully do?
Decode fully repeats the selected decode operation until the text stops changing or five passes have run. It is useful for repeatedly encoded input, but it does not bypass malformed percent escapes.