URL Component Encoder & Decoder
Encode one URL component as UTF-8 percent escapes or decode one layer. Includes live output, examples and clipboard copying.
About this url component encoder & decoder
Encode one URL component as UTF-8 percent escapes or decode one layer. Includes live output, examples and clipboard copying.
How this tool works
Encode follows ECMAScript encodeURIComponent: ASCII letters, digits and -_.!~*'() remain unchanged; other Unicode characters become UTF-8 bytes written as %HH. Decode follows decodeURIComponent, resolves one layer of percent escapes and rejects incomplete triplets or invalid escaped UTF-8. A literal + remains +. This component transformation does not parse or validate a complete URL.
- Choose Encode and enter summer sale & more. The output updates immediately.
- Read summer%20sale%20%26%20more; Copy places this exact component in the clipboard.
- Choose Decode and enter that encoded output to recover the phrase. Load sample fills the example for the selected mode.
Worked example
Scenario: Prepare a search phrase to use as one query parameter value.
Sample input:
Processing: Each space becomes %20 and the ampersand becomes %26. Decode applies one inverse percent-encoding layer.
Illustrative output:
Limits and verification
This is component encoding, not encryption, sanitization, a URL safety check or a form serializer. It leaves !'()* unchanged and therefore is not a strict RFC 3986 unreserved-only encoder. Form-style + handling is unsupported. Decode once for the representation your application expects; repeated decoding can change delimiters. Textarea line endings normalize to LF. No file input or download is provided; large inputs are limited by browser memory and responsiveness.
Examples demonstrate an expected workflow; they do not prove every input or every branch of an external specification. Check important results with an independent source before using them for money, security, compliance, safety, or irreversible file changes.
Browser processing boundary
Tool input is processed by code running in the browser and is not intentionally sent to a CZOA processing API. The page can still request ordinary site assets, analytics, or advertising when those services are enabled. Browser extensions and managed-device software remain outside this tool's control.
Relevant references
These references govern or help explain the format, protocol, or calculation used here. Listing a reference does not claim certification or complete implementation of every optional feature.
- ECMAScript: encodeURIComponent / decodeURIComponent
- RFC 3986: percent-encoding and component boundaries
Content owner: CZOA Tools · Review methodology
How to use it
- Choose Encode and enter summer sale & more. The output updates immediately.
- Read summer%20sale%20%26%20more; Copy places this exact component in the clipboard.
- Choose Decode and enter that encoded output to recover the phrase. Load sample fills the example for the selected mode.
Frequently asked questions
What does URL Encoder encode?+
It uses the browser component encoder for the entered text; Decode uses the matching component decoder. It does not parse or fetch a whole URL.
What local example can I run?+
In Encode mode, enter `summer sale & more` → `summer%20sale%20%26%20more`.
How are plus signs and spaces handled?+
Encode turns a literal `+` into `%2B` and a space into `%20`. Decode preserves a literal `+`; it does not apply form-style plus-to-space conversion.
How are decode errors handled?+
Incomplete percent escapes or percent bytes that are not valid UTF-8 show an error instead of a decoded value. For example, `%ZZ` and `%E2%82` fail.