Defaults.Exposed › By TLD › .io
Is .io safe? The state of .io domain security
.io is about average for the internet. Across 958,000 graded .io domains, 71.6% score an F — roughly in line with the 73.8% global average. 3.2% earn a B or better. Most .io domains can still be impersonated in email, but the ending shifts the odds, not your own domain's grade. As of 2026-07-29.
How do .io domains score?
Aggregate grade distribution across all graded .io domains — we never publish an individual business's grade. As of 2026-07-29.
| Grade | Domains | Share |
|---|---|---|
| A+ | 856 | 0.1% |
| A | 2,866 | 0.3% |
| B | 27,405 | 2.9% |
| C | 89,725 | 9.4% |
| D | 150,997 | 15.8% |
| F | 686,151 | 71.6% |
Does .io 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 .io doesn't protect you, and a high-F-share ending doesn't doom you: a correctly configured .io domain earns an A while the crowd around it sits at F.
Want to know where your .io 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 .io safe?
On average, .io is about average for the internet: 71.6% of its 958,000 graded domains score an F as of 2026-07-29, against a 73.8% global average. Most domains on every ending are exposed — the ending shifts the odds, not your own domain's grade.
How secure are .io domains?
28.4% of .io domains score above an F and 3.2% 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 .io 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 .io too.
What does "grade F" mean for a .io 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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