Free DNS and SSL checker

Check any domain's website, SSL certificate and email records in one go, with a plain-English verdict on each. Free, no sign-up, and it works for domains hosted anywhere.

What this checker looks at

• A and AAAA records point your domain at the server that holds your website. Without an A record, nobody can reach the site.
• www is a separate name. If it has no record, anyone who types www in front of your domain gets an error.
• SSL certificate: browsers expect HTTPS. We check the certificate is trusted, covers your exact domain and is not about to expire.
• MX records tell the world which servers accept email for your domain.
• SPF and DMARC are TXT records that prove mail from your domain is genuine. Without them, Gmail and Outlook are far more likely to send your messages to spam. You should have exactly one SPF record.
• CAA records (optional) limit which certificate authorities can issue certificates for your domain.
• DNSSEC (optional) signs your DNS answers so they cannot be forged.

Fixing what it finds

DNS records are changed wherever your domain's DNS is managed, which is usually the company you bought the domain from. Look for a "DNS", "Zone" or "Manage DNS" page. Changes normally reach everyone within an hour, and at most within a day or two.

If your site or email is hosted with THOST, our Connect your domain tool adds the right records for you at many DNS providers, and every THOST plan includes free SSL that renews itself. Stuck? Email support@t-host.co.uk and we will tell you what to change, whoever hosts your domain.

The checker does not save the domains you check, although like any page request they appear in our web server logs for about 10 days (see our privacy policy). Lookups are limited to 20 every ten minutes per visitor.