Free URL Encoder and Decoder Online

URL encoding (also called percent-encoding) converts characters that are not allowed or have special meaning in a URL into a format that can be safely transmitted. Each unsafe character is replaced by a % followed by its two-digit hexadecimal code. For example: space becomes %20, & becomes %26, = becomes %3D, # becomes %23, and / becomes %2F.

tools.ubify.app encodes and decodes URLs entirely in your browser — no data is transmitted to a server.

URLs can only legally contain a subset of ASCII characters as defined by RFC 3986. Characters fall into three categories. Reserved characters have special meaning in URL structure and must be encoded when used as data: ! * ( ) ; : @ & = + $ , / ? # [ ]. Unreserved characters are safe without encoding: A-Z, a-z, 0-9, hyphen, underscore, period, tilde. Everything else must be percent-encoded, including spaces, non-ASCII characters (accented letters, Chinese, Arabic, emoji), and most punctuation.

The tool supports two encoding modes. Component encoding encodes everything including /, ?, and & — use this for individual query parameter values. Full URL encoding preserves URL structure characters while encoding only unsafe characters within each component — use this for complete URLs. In JavaScript, encodeURIComponent() handles component encoding; encodeURI() handles full URL encoding.

A common confusion: in query strings, a space can be encoded as either %20 or +. The + encoding comes from HTML form submissions. In URL paths (before the ?), only %20 is valid for spaces — a + in a path means a literal plus sign. When in doubt, use %20 — it works in all contexts.

For non-ASCII characters such as accented letters, emoji, or CJK characters, the process is: first convert to UTF-8 bytes, then percent-encode each byte. The euro sign € is UTF-8 bytes E2 82 AC, which encodes as %E2%82%AC. The Japanese character 日 is UTF-8 bytes E6 97 A5, encoding as %E6%97%A5. Our encoder handles all Unicode automatically.