A cold-email domain fleet should be checked as an inventory, with one row per domain and per sending provider. Record SPF lookup count, DKIM selector and key resolution, DMARC policy and alignment, MX, sending-IP PTR where applicable, TLS reporting, MTA-STS, and timestamped blocklist responses. A green DNS row means authentication readiness only; it does not predict replies or inbox placement.
Fleet problems hide in exceptions. Twenty domains may share one template while three use an old provider, two publish duplicate SPF records, and one signs with an unrelated domain. A spreadsheet makes those differences visible and gives each proposed DNS record an owner, provider, and validation state.
What the record changes
The safest workflow imports the domain list, discovers public records, asks the operator to confirm the sender mapped to each domain, and writes changes only after that map exists. Validate in small batches so one template error cannot propagate to 150 domains. Blocklist results carry the list name and time because a clean response is momentary, not permanent.
- The offer's multi-domain tiers cover up to 25 or 150 domains because one-at-a-time free checkers become operationally expensive at fleet size.
- SPF, DKIM, and DMARC checks are deterministic from public records, but active-sender inventory still requires operator confirmation.
- Mail-law consent, targeting, and content remain outside this report, and the operator remains responsible for them.
How to use this answer
An authentication check reads the domain's published SPF, DKIM, DMARC, MX, TLS reporting, MTA-STS, and related records, then validates syntax and relationships. The fix block contains proposed records for the customer's actual provider and order of operations. A domain can pass these checks and still reach spam, because reputation, volume, content, consent, and list quality live outside DNS.
- Check the visible From domain, sending service, return path, and DKIM signing domain before changing any record.
- Read the existing DNS, count SPF evaluation terms, find DKIM selectors, and evaluate DMARC alignment and reporting addresses.
- Apply one reviewed change at a time, wait for DNS propagation, and validate the published result before tightening policy.
Where the service stops
Reality Contact, LLC reads public DNS and public blocklist responses. We never log into your DNS, mail server, or sending platform, and we never send from your domain. You paste the proposed records. The scope is authentication-ready, not inboxing. List quality, content, volume, and sender reputation are outside what DNS can show. This is not legal advice, and mail-law compliance remains yours.
Sources: Google email sender guidelines; Yahoo sender best practices; RFC 7489: DMARC.