URL Encoder/Decoder

Encode and decode URLs and query parameters. Component or full URL modes.

Runs 100% client-side
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On this page4 sections
Input
Output

HOW TO USE

  1. 01Paste a URL or query parameter value into the input area.
  2. 02Use Encode Component / Decode Component for query string values — encodes :/?#&= too. Use these for individual parameter values.
  3. 03Use Encode Full URL / Decode Full URL when working with a full URL — preserves the protocol, slashes, and reserved characters.
  4. 04Click Swap to move the output back to the input for chained transforms.

WHEN TO USE

Use this when constructing or debugging URLs that contain special characters in query parameters, path segments, or fragment identifiers. A space, &, =, or # in a query value that isn't encoded becomes a structural character and breaks URL parsing — this tool shows the encoded form before you embed it. Use Decode when a URL in a log or error message is percent-encoded and you need to read the original value. Use 'Encode Component' for individual parameter values and 'Encode Full URL' for a complete URL you want to preserve intact.

WHAT BUGS THIS FINDS

  • Query parameter truncation on special characters

    An unencoded & in a parameter value silently splits it into two parameters — Encode Component shows the correct %26 form that the server will parse as a single value.

  • Double-encoding artifacts

    Encoding an already-encoded URL produces %2520 for a space instead of %20 — Decode first to check whether the value is already encoded before encoding again.

  • Space encoded as + vs %20

    Form submissions encode spaces as + while RFC 3986 URLs use %20 — the wrong choice breaks servers that don't normalise; Encode shows the exact RFC form.

  • Reserved characters in wrong context

    Encoding a full URL with Encode Component converts / to %2F, breaking the path — 'Encode Full URL' preserves structural characters while encoding only the parameter values.

QA USE CASES

01

API query string construction

Encode individual parameter values containing &, =, or special characters before embedding them in a query string, then paste the encoded form into your API call or test fixture.

02

Redirect URL debugging

Decode a percent-encoded redirect_uri from an OAuth error log to confirm the URL it's trying to redirect to and whether it matches the registered allowlist.

03

Webhook and callback URL nesting

Encode a callback URL that contains query parameters before passing it as a value in another URL — confirms the nested URL is safely wrapped for the outer request.