Are all your domains safe?
Paste every domain you own. Warnwell tells you, in plain words, which ones are about to expire, which websites are broken, and which ones anyone can use to send fake email in your name. Each problem comes with the exact fix.
Free. No sign-up. Up to 50 domains at once.
Four things that quietly go wrong
Renewal
A card expires, an old email stops being read, and a domain lapses. Warnwell reads the expiry date from the registry, says how many days are left and where it is registered, flags a missing transfer lock, a brand-new domain or a recent move to another registrar, and gives you a calendar file with a reminder 30 days before each date.
Website
It opens your site the way a visitor does: with and without www, over http and https. It reports a certificate that is broken or about to run out, DNS that is signed wrong (DNSSEC), an error page, a redirect chain, or a registrar parking page full of ads where your site should be.
Most domains, including ones that send no mail at all, let anyone send email "from" them. Warnwell reads SPF, DMARC, MX and DKIM and tells you whether fakes are delivered, sent to spam or rejected, and whether your own mail is signed, then gives you the records to copy.
Reputation
A hacked site or a spam complaint can get a domain blocked. Warnwell asks Cloudflare's malware filter whether it blocks your domain, and links to the Spamhaus and SURBL lookups so you can check the spam lists yourself.
Questions
- Who is this for?
- Anyone who owns more than one domain: small businesses with a few brand names, agencies looking after client domains, founders with old projects, and people who bought a domain years ago and forgot about it.
- What happens to the list I paste?
- Nothing is saved. Your list stays in your browser (it sits after the # in the address, which browsers never send to a server). Each domain is checked live from public sources, and the answer is kept in a cache for ten minutes so a reload is instant.
- Where does the information come from?
- The expiry date and registrar come from the registry over RDAP, the public replacement for WHOIS. DNS records come from a public resolver. The website check opens your site like a browser does; certificate dates come from the public Certificate Transparency logs, and the malware hint from Cloudflare's 1.1.1.2 filter. Some country registries, such as .io and .dk, do not publish expiry dates; Warnwell says so instead of guessing.
- Why would someone fake email from a domain I do not even use?
- Because nobody is watching it. A domain without a DMARC "reject" policy is an easy way to send convincing invoices or password resets. The fix for an unused domain takes three DNS records. How to lock down a domain that sends no mail.
- Can my AI assistant run this?
- Yes. Warnwell is also an MCP server, so Claude, ChatGPT, Cursor and other agents can check domains and read the fixes. Connect it.
- What does it not check?
- The spam blocklists themselves: their terms do not allow lookups for a service like this, so Warnwell links you to Spamhaus and SURBL instead. DKIM keys under names of your own (it tries the common ones), and uptime over time. It reads what anyone can see; it never logs in anywhere or changes anything.