Non-ASCII URL boundary · Updated November 7, 2026

Non-ASCII Characters in URLs: Inspect UTF-8 Encoding

Paste text to see which characters are outside ASCII and how their UTF-8 bytes become percent escapes. The report separates ordinary ASCII, non-ASCII code points, bytes, and URL output so one character is not mistaken for one byte.

Text or URL component

Four inputs, four byte lengths

Input	Code point	UTF-8 bytes	Encoded
`é`	`U+00E9`	`C3 A9`	`%C3%A9`
`€`	`U+20AC`	`E2 82 AC`	`%E2%82%AC`
`中`	`U+4E2D`	`E4 B8 AD`	`%E4%B8%AD`
`A`	`U+0041`	`41`	`A`

Non-ASCII is not one single URL rule

Path and query components can percent-encode UTF-8 bytes, while a Unicode hostname is serialized with IDNA/Punycode. Inspect the URL part first; do not apply a path encoder to a hostname or treat a byte count as a character count.

Rerun the evidence

Download the Node regression script, fixtures and recorded results. Run node non-ascii-characters-regression.cjs with Node v24.19.0.

For direct UTF-8 byte output, use Encode UTF-8 for a URL; for hostname boundaries, use IDN hostname checks.