Technical stack checkup
No signup. Enter a URL and get a result you can actually act on.
Five free checkers
Every one of them is built in-house rather than resold from a paid API — which is why they can stay free.
Website speed check
Enter a URL and get a 12-metric report in 10–30 seconds — not a score for engineers, but a plain answer to what is slow and what to fix first.
DNS records lookup
See a domain's DNS records, plus a quick check on SPF, DMARC and CAA for email.
SSL certificate check
Issuer, validity dates, covered domains and the full chain — catch expiry and mismatches early.
HTTP response header check
See exactly what the server returns: security headers, caching, compression and the full redirect chain.
Structured data check
Check a page's JSON-LD: syntax, types, required fields, and whether it matches the visible content.
How it works
Pick a tool
DNS, certificate, response headers or structured data.
Enter a URL
A bare domain or a full URL both work, e.g. example.com.
Read the result
Each finding is rated by severity, with a fix direction.
Other free tools
FAQ
Is it really free?
Yes — all tools are free and need no signup. They run on our own implementation, so there is no paid API quota to burn.
How long does a check take?
DNS and headers usually 1–3 seconds; certificates 1–5 seconds; structured data downloads the whole page, so 2–8 seconds.
Do you store the sites I check?
Nothing is published. Results are cached in server memory for a few hours only, to avoid repeat checks.
Can I check someone else's site?
Yes, as long as it is publicly reachable. We only check public addresses — internal and server-side addresses are rejected.
Found problems — now what?
The report tells you what is wrong. If you want someone to fix it, with priorities and acceptance criteria, take a look at our services.