api-2316b762.duosecurity.com is a subdomain of Duo Security, a respected cybersecurity company owned by Cisco. It redirects to the main duo.com site, which is exactly what you'd expect from an internal API or redirect endpoint. The security setup is solid: a valid certificate, enforced HTTPS, and no blacklist or malware flags. This isn't a site you'd browse directly — it's part of the infrastructure behind Duo's authentication services. For that purpose, it looks clean and well-maintained. The lack of a favicon or web archive history might raise an eyebrow, but for a technical subdomain that's not meant to be visited by users, those are normal. If you're wondering whether api-2316b762.duosecurity.com is a scam or fake, there's nothing here to suggest it is. It's a legitimate component of a major security brand. As always, when dealing with any site that handles logins or sensitive data, make sure you're on the official domain — but in this case, the redirect to duo.com is a good sign.
In plain English
This is a legitimate subdomain of Duo Security, a well-known cybersecurity company now part of Cisco. The site redirects to duo.com and has strong security in place. It's a behind-the-scenes API endpoint, not a consumer-facing site, and everything checks out fine.
Where the score comes from
Strong security setup: valid certificate from a trusted issuer, enforced HTTPS, and modern web protections. No malware or phishing flags. This is exactly what you'd expect from a legitimate company's infrastructure.
The subdomain is part of duosecurity.com, a well-known security provider owned by Cisco. WHOIS for the subdomain isn't available, but that's normal for a technical endpoint. The parent domain's identity is clear and reputable.
The domain is not blacklisted and has no history of abuse. The lack of web archive snapshots is typical for a dynamic API endpoint, not a sign of anything shady. No external trust signals, but that's fine for a behind-the-scenes service.
This subdomain doesn't present its own about page or contact info, but it redirects to duo.com, which has full transparency. For an API endpoint, that's expected and acceptable. The parent company is open about its identity.
No legal pages are present on this subdomain, but it's not a consumer-facing site — it's a redirect to Duo's main site, which has privacy policy, terms, and compliance information. This is standard for infrastructure domains.
DNS resolves to two IPs on Amazon's network, which is reliable. The server software is named 'Duo/1.0', consistent with the company. Robots.txt is present with many directives, indicating active management. No email setup, but that's not needed here.
What we checked
Run this site? Show your score.
Add a trust badge so visitors can see your live score for themselves.
Get your badge →