Free URL check
Status, certificate, and the text we'd watch.
Paste a public page. You get the HTTP status, how long it took, how many days the TLS certificate has left, and the visible text a monitor would hash. No account. Watching it on a schedule — change, downtime, and certificate expiry — is the free plan.
Free is 3 URLs, every 15 minutes. Each one alerts on text changes, downtime, and when the certificate is inside 14 days, then again inside 3.