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Email deliverability check
Enter any domain. We check its SPF, DKIM, DMARC and MX records and look it up on the main blocklists, live, in a few seconds.
What a cold email domain needs to pass
- MX: the domain must receive mail, so replies arrive and filters see a real mailbox.
- SPF: exactly one
v=spf1record naming your mail provider, ending in~allor-all. - DKIM: your provider signs every message; the public key lives at
selector._domainkey. - DMARC: required by Gmail and Yahoo for bulk senders since February 2024, and by Outlook.com since May 2025.
- Blocklists: a listing on Spamhaus or similar sends mail to spam at many receivers.
Need sending domains that pass all of this from day one? ReplyDak sets up domains, DNS and Google Workspace mailboxes automatically. You can also find available lookalike domains.
Questions
What does this deliverability check test?
Five things, live from public DNS: MX records (can the domain receive replies), SPF (one valid record, under 10 lookups, not +all), DKIM (a key at common selectors such as google or selector1), DMARC (one record with a valid policy) and domain and mail-server IP blocklists (Spamhaus DBL and ZEN, SURBL, URIBL, SpamCop, Barracuda).
Why does DKIM say not found when I have it?
DNS can't list DKIM selectors, so we try the common ones. If your provider uses a custom selector, open a message you sent, find the DKIM-Signature header and look at s=; that is your selector.
Is p=none DMARC good enough?
It meets Gmail and Yahoo's bulk-sender rule that a DMARC record must exist, but it doesn't protect the domain. Start with p=none while warming up, then move to p=quarantine once SPF and DKIM pass.
What if a blocklist couldn't be queried?
Some blocklists refuse lookups from busy shared resolvers. We show those as not checked rather than guessing; try again later or check that list's own lookup page.
Do I need to sign up?
No. The check is free and needs no account. ReplyDak sets all of these records up automatically on the sending domains it creates for you.