Small tools, no signup
Three things we needed often enough to build properly. They run on the same code as the monitoring — a tool that answers differently from the product is worse than no tool.
SSL certificate checker
One real handshake: issuer, expiry date, days left and the TLS version a hostname actually serves.
Is the certificate on the wire valid, and how long have I got?
HTTP status checker
One GET from our servers: status code, response time, the whole redirect chain and where it ends up.
What does an anonymous client on another network actually get?
Cron expression generator & tester
Build an expression from a schedule you can say out loud, or paste one and see the next ten run times in your own time zone.
How do I write "every day at 2:00" — and when does it actually fire?
Why we run these for free
Because each one stops one step short of the thing we sell, and the gap is honest. The SSL checker tells you the certificate is valid now; it cannot tell you it was still valid at 4 a.m. on Sunday. The HTTP checker answers from one place at one moment; the failures that cost money — one bad node out of four, a regional routing problem, a slow leak from 200 ms to 2 s — look healthy from a single probe. The cron tester says when an expression fires, not whether the job ran.
Monitoring is the same questions asked on a schedule, from several regions, with an alert when the answer changes. If a one-off check is all you needed, these pages are the whole product and you owe us nothing.
If you saw our checker in your logs
Requests from these tools identify themselves as
CronAliveSiteCheck/1.0 and are
triggered by a person typing your hostname into one of the
pages above — one GET, never more than three redirects, no
crawling, no forms submitted, no credentials. Results are
cached for ten minutes and the number of requests to any one
host is capped, so this cannot be used to hammer you.
Questions or a complaint: write to us.