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Will your cold emails land in the inbox?

Enter a sending domain. You get a grade for the DNS records that decide whether your mail authenticates, and the exact fix for anything broken.

What it checks

SPF

Which servers may send for your domain. Catches the 10-DNS-lookup limit that silently breaks SPF once you add one tool too many.

DKIM

The signature that proves your mail wasn't altered. Looks for a valid key at your provider's usual selector.

DMARC

What inboxes should do with mail that fails SPF/DKIM. Gmail, Yahoo and Microsoft now require it for bulk senders.

MX

Where replies go. No MX means replies and bounces are lost, which also looks bad to spam filters.

Lookups run over DNS-over-HTTPS. Checks aren't saved; if you ask for the report by email, I keep your email, domain and results so I can reply. Powered by coldwatch, my open-source checker.