What we observed
Looking at duo.com from the outside, the most important data points are its hosting country (United States), the SSL state (OK) and the registration footprint (MarkMonitor Inc.).
Encryption (HTTPS)
HTTPS check returned OK. A valid TLS certificate is the bare minimum any modern site should ship — its absence is a serious red flag.
Time on the open web
duo.com has been visible to public DNS for roughly 27.7 years. That is enough history to leave a reputation footprint, which we factor into the score.
Hosting & infrastructure
The domain currently resolves to a server in United States, served by Unknown. Hosting location does not equal trust, but it tells you which jurisdiction handles the data.
Comparable domains
Sites with similar metadata to duo.com — 27.7 yrs, United States hosting, valid SSL — typically include both legitimate businesses and rebranded shells. Treat the score as one signal among several.
Conclusion
After fusing DNS, TLS, RDAP and GeoIP signals, our automated score for duo.com sits at 100/100 (very_safe). Use it as a guideline, not a guarantee.