Free · no account
Is your website quietly in trouble?
Type an address. In about 15 seconds you see whether the site answers and how fast, when its SSL certificate and domain expire, which common security headers are missing, whether search engines are told to stay away, and whether SPF and DMARC stop others sending email in its name.
What the check looks at
- Does it answer. One request to the address you typed, following redirects, with a 10-second limit. A 403 or 503 is flagged separately — it is often a firewall answering an automated check while people see the page normally.
- SSL certificate. The expiry date and issuer, read from the TLS handshake. Free certificates renew about 30 days before expiry, so fewer than 21 days left usually means renewal is failing.
- Domain registration. The expiry date, asked from the domain's own registry over RDAP (Nominet for .uk, Verisign for .com). An expired domain takes the website and the email down together.
- Security headers. Strict-Transport-Security, Content-Security-Policy, X-Content-Type-Options, clickjacking protection and Referrer-Policy.
- Search engines. Whether the page or its headers say
noindex— the staging setting that sometimes survives a launch. - Email authentication. The SPF and DMARC records of the domain, which decide whether somebody else can send email that looks like yours.
What it does not do
It is one look from one place. It does not log in, fill in forms, scan for vulnerabilities or test every page — and a site that is fine now can break an hour later. Nothing is stored about the site you check, and the check sends no cookies or credentials.
To be told the moment something changes, MySentry watches the site around the clock: uptime every 5 minutes, certificate and domain expiry, changes to the page and its headers, and — with the WordPress plugin — errors, failed emails and waiting updates.