An Internationalized Resource Identifier, defined in RFC 3987, is a URI that may contain Unicode characters directly — for example a path with Cyrillic or Chinese text. IRIs are easier for people to read, but many systems still require a plain ASCII URI.

How does IRI-to-URI conversion work?

Each character that is not in the allowed ASCII URI set is converted to its UTF-8 byte sequence, and each byte is percent-encoded as %XX. Characters that are already valid in a URI — letters, digits, and reserved delimiters like the slash and question mark — are left untouched so the URL structure is preserved.

Does this encode the domain name too?

This tool percent-encodes the path, query, and fragment. Internationalized domain names use a different scheme called Punycode (xn-- prefixes) rather than percent-encoding, so the host portion of an IRI is handled separately by IDNA, not by this converter.

Will reserved characters like slash and ampersand be encoded?

No. Reserved URI delimiters such as slash, question mark, hash, ampersand, and equals are preserved because they carry structural meaning. Only characters outside the unreserved and reserved ASCII sets are percent-encoded.

Is anything sent to a server?

No. The conversion runs entirely in your browser with JavaScript, so the URLs you process never leave your device.

IRI Encoder (RFC 3987)

An IRI (Internationalized Resource Identifier, RFC 3987) is a URL that may contain Unicode — handy for humans but not always accepted by strict clients. This tool converts an IRI to a plain ASCII URI by percent-encoding the non-ASCII parts, in your browser.

How it works

The conversion walks the IRI character by character:

Characters in the allowed ASCII set — unreserved (A-Z a-z 0-9 - . _ ~) and reserved delimiters (: / ? # [ ] @ ! $ & ' ( ) * + , ; = and %) — are left as-is so the URL structure stays intact.
Every other character (any non-ASCII, plus ASCII space and control characters) is encoded to its UTF-8 bytes, and each byte becomes %XX.

This is exactly the IRI-to-URI mapping from RFC 3987: it preserves the scheme, host separators, and query structure while making the identifier safe for systems that only accept ASCII URIs.

Tips and examples

The IRI https://example.com/café?q=naïve becomes https://example.com/caf%C3%A9?q=na%C3%AFve — the é and ï are encoded as their two-byte UTF-8 sequences, while the scheme, slashes, and the ? and = delimiters are untouched. Note that internationalized host names (the domain itself) are converted with Punycode (xn-- labels) by IDNA, not by percent-encoding, so this tool focuses on the path, query, and fragment.