Is anything I paste here uploaded?

No. Encoding and decoding run entirely in your browser via the native encodeURIComponent, encodeURI, decodeURIComponent, and decodeURI functions. Nothing is sent to any server.

When should I check Whole URI instead of the default component mode?

Use component mode (the default) for individual values like query parameters — it encodes reserved characters such as /, ?, &, and =. Check Whole URI when you have a complete URL and want to keep its structure intact; encodeURI leaves those delimiters alone and only escapes characters that are invalid in a URI.

Why does decoding sometimes fail with an error?

A percent sign must be followed by two hex digits. Sequences like %ZZ or a trailing lone % form a malformed escape, and decodeURIComponent throws — the tool shows "Invalid input for decoding" instead of a result.

URL Codificar / Decodificar

Overview

Percent-encoding represents unsafe or reserved characters as %XX hex escapes so they can travel safely inside URLs. This tool wraps the browser’s native functions: component mode uses encodeURIComponent / decodeURIComponent, and Whole URI mode uses encodeURI / decodeURI, which preserves structural delimiters like :, /, ?, and &.

How to use

Select Encode or Decode with the mode tabs.
Leave Whole URI (encodeURI) unchecked to encode a single component (query value, path segment), or check it to process a full URL without breaking its delimiters.
Type or paste into Input — the Result field updates as you type.

Examples

Component encode: a b&c=1 → a%20b%26c%3D1
Whole URI encode: https://example.com/?q=a b → https://example.com/?q=a%20b (the ://, ?, = survive)
Decode: caf%C3%A9 → café

Notes

Encoding an already-encoded string double-escapes it (%20 becomes %2520), which is a common source of broken links. Non-ASCII input is encoded as UTF-8 bytes, so one character may expand to several %XX sequences.