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Is .cz safe? The state of .cz domain security — Czechia
.cz is safer than the internet average. Across 1,266,593 graded .cz domains, 68.9% score an F — cleaner than the 78.3% global average — better company than most of the web. 2.4% earn a B or better. Most .cz domains can still be impersonated in email, but the ending shifts the odds, not your own domain's grade. As of 2026-08-16.
In the .cz zone — covering Czechia — 62.5% of 932,544 graded domains earn an F, well below the 73.8% internet-wide average. DNSSEC adoption is 63.1% here, notably higher than the 6.3% census-wide rate.
Note: .cz is used as a proxy for Czechia based on the domain's TLD, not where the company is registered.
How do .cz domains score?
Aggregate grade distribution across all graded .cz domains — we never publish an individual business's grade. As of 2026-08-16.
| Grade | Domains | Share |
|---|---|---|
| A+ | 777 | 0.1% |
| A | 2,184 | 0.2% |
| B | 27,736 | 2.2% |
| C | 146,598 | 11.6% |
| D | 216,778 | 17.1% |
| F | 872,520 | 68.9% |
Does .cz make a domain secure?
No — and that's the most important thing to know. A domain's grade is decided by how it is configured (SPF, DMARC, HTTPS, DNS), not by its ending. Choosing .cz doesn't protect you, and a high-F-share ending doesn't doom you: a correctly configured .cz domain earns an A while the crowd around it sits at F.
Want to know where your .cz domain ranks? Check it privately and free — we only ever show an individual domain's grade to its verified owner. Run the free check →
Frequently asked questions
Is .cz safe?
On average, .cz is safer than the internet average: 68.9% of its 1,266,593 graded domains score an F as of 2026-08-16, against a 78.3% global average. Most domains on every ending are exposed — the ending shifts the odds, not your own domain's grade.
How secure are .cz domains?
31.1% of .cz domains score above an F and 2.4% earn a B or better. The rest fail the basic externally observable protections, most importantly enforced SPF and DMARC, so they can be impersonated in email.
Does choosing .cz make my domain secure?
No. A domain's grade comes from how it is configured — SPF, DMARC, HTTPS, DNS — not from its ending. A well-configured domain earns an A on any ending; an unconfigured one sits at F on .cz too.
What does "grade F" mean for a .cz domain?
It fails the basic protections we can observe from outside — above all, it has no enforced SPF and DMARC, so its email can be forged and its customers targeted with convincing fakes.
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