Toolvantas

Developer utility

URL Encoder and Decoder

Encode special characters into RFC-compliant percent-encoded format or decode URLs back into clean text. Includes standard selection, form + space control, and live query parameter parsing.

Input Characters0
Output Characters0

How URL percent-encoding works

Uniform Resource Identifiers (URIs) must adhere to the ASCII character set. Characters outside ASCII, as well as reserved structural delimiters, are converted into UTF-8 byte sequences prefixed with %.

  • Spaces: Encoded as %20 in RFC 3986 URIs (or + in HTML form query strings).
  • Query Delimiters: & becomes %26, = becomes %3D, and ? becomes %3F.
  • Slashes & Protocols: / becomes %2F and : becomes %3A when encoded with encodeURIComponent.

encodeURI vs. encodeURIComponent

Choosing the right encoding mode prevents broken links and query injection bugs:

  • Use encodeURI: When encoding a complete clickable URL (such as https://example.com/docs/my guide.pdf). It keeps https://, slashes, and ? intact while encoding spaces and Unicode characters.
  • Use encodeURIComponent: When encoding an individual query parameter value (such as passing a callback URL or search term containing & or =).

Frequently asked questions

Why do URLs need to be percent-encoded?

URLs can only travel across HTTP/HTTPS networks using ASCII characters. Encoding ensures international characters, spaces, and reserved symbols do not break web server routing or API parameter structures.

What is the difference between encodeURI and encodeURIComponent?

encodeURI preserves structural URL delimiters like :, /, ?, and &, while encodeURIComponent encodes those characters so a single query value cannot break surrounding URL syntax.

Should plus (+) signs be decoded as spaces?

HTML form submissions (application/x-www-form-urlencoded) turn spaces into +, while strict RFC 3986 paths treat + as a literal plus sign (e.g., C++). Toggle the checkbox depending on your source string.

What does the Parsed Query Parameters table show?

When an input or decoded URL contains query arguments (such as ?user=123&category=books), the inspector parses each key-value pair into an easy-to-audit table.

Are my URLs or API tokens sent to any server?

No. All conversions and parameter extractions take place locally inside your browser. None of your links or query tokens are transmitted over the network.

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