Disclosure
Disclosure
Transparency about links, funding, scope, and your data — per FTC guidance.
urldiffer is free. Some outbound links — for example to security testing tools, hardened URL libraries or learning resources —
may be affiliate links: if you sign up through them we may earn a commission at no extra cost to you. Paid links
are marked rel="sponsored nofollow".
We only link to things we'd actually use, and a commission never changes what the tool reports.
Scope & not a safety guarantee. urldiffer computes two exact parsers (WHATWG and RFC 3986) and explicitly-defined naive checks for your input; it does not run other languages’ libraries, does not fetch the URL, and a green result is not a proof your application is safe. Test against the real libraries in your stack for production decisions.
Your privacy: this is a static, client-side tool. The URL you paste is processed in your browser and is never uploaded or fetched — there is no backend and nothing is logged.