About Certly

Certly is a monitoring service for the two deadlines that take websites offline without warning: the SSL certificate and the domain registration. It is built and operated by IncreoScale, a small software company in Tokyo.

Why we built it

Expired certificates are not an exotic failure. They happen to teams who know exactly what a certificate is — we have written about a national research institute that runs its own certificate authority being caught by one. Auto-renewal is not the safety net it looks like: the renewal runs, the new certificate never reaches the server, and nothing tells you until a customer sends a screenshot of a browser warning.

That gap is getting wider. The CA/Browser Forum has agreed to cut maximum certificate lifetimes from 398 days to 47 by 2029, which means roughly eight times as many renewals — and eight times as many chances for one to fail quietly. Certly exists to close the gap between "the renewal ran" and "the certificate your server actually serves is valid."

What we watch

• SSL certificates — the certificate your server actually delivers, not the one a registry says should be there.
• Domain registration — expiry dates, plus the registry (EPP) status codes that can suspend a domain while the registration is still valid.
• DNS and DNSSEC — every record change on a timeline, and DNSSEC signature expiry, which takes a site down completely and silently.
• Email spoofing exposure — whether DMARC and SPF are published and actually enforced for your domain.

Alerts arrive by email on every plan; paid plans add Slack, Discord, and webhook delivery with staged 30/14/7/1-day alerts. You can run a free check on any domain without an account, or explore the dashboard before signing up.

How we work

• We check what is actually served. A monitor that reads registration paperwork cannot tell you that the renewed certificate never made it onto the load balancer.
• We publish our reasoning. Our writing on certificate and domain incidents cites primary sources — CA/Browser Forum ballots, registry records, operator statements — so you can check the work rather than take our word for it.
• We keep pricing flat and legible. Plans are per account, not per seat, and start free for two sites.

Operator information

• Business name: IncreoScale (Representative: Fumiya Koizumi)
• Address: Magazan Sangenjaya 2 3F-3, 4-18-15 Taishido, Setagaya-ku, Tokyo 154-0004, Japan
• Email: support@certly.dev

Full legal detail lives in our Terms of Service and Privacy Policy.

Contact

Questions, bug reports, and "does Certly handle…" emails all go to the same place: support@certly.dev. A person reads them.