How to use the email deliverability checker
- Type the domain you send from (or any email address on it).
- Press Check domain and wait a few seconds for the live DNS lookups.
- Read each result: Pass, Warning, Missing or Could not check.
- Copy the suggested record into your DNS host for anything marked Missing, then check again.
What the results mean
Each record does a different job, and inbox providers look at all of them together.
- SPF lists the servers allowed to send for your domain. You need exactly one SPF record.
- DKIM signs every email so inboxes can tell it was not changed in transit.
- DMARC tells inboxes what to do when SPF or DKIM fail, and where to send reports. Google and Yahoo require it for bulk senders.
- MX shows where the domain receives email; a sending domain with no MX looks suspicious to spam filters.
How to fix common issues
Most problems take a few minutes in your DNS settings. If DKIM shows a warning, your email host may use a selector the checker does not test; turn DKIM on in the host's settings and copy the record it gives you. After fixing DNS, warm up a new mailbox slowly before sending at volume: our email warmup guide explains the schedule, and Contractor Leads checks these records for every connected mailbox automatically.
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FAQ
- Is this SPF, DKIM and DMARC checker free?
- Yes. It is free with no sign-up and no limit beyond a few checks per minute to prevent abuse. It only reads public DNS records and does not store the domains you check.
- Why does DKIM show a warning when I set it up?
- DKIM lives under a selector name that only your email host knows. The checker tests the selectors used by Google Workspace, Microsoft 365, Hostinger and other common hosts. If yours uses a different one, DKIM may still be working; check your host's DNS page to confirm.
- Which DMARC policy should I use for cold email?
- Start with p=none and a reporting address so you can see who sends as your domain without blocking anything. Once reports show only your own services, move to p=quarantine. Google's sender guidelines require at least p=none for bulk senders.
- Do I need these records to send cold email?
- Yes. Without SPF and DKIM, Gmail and Outlook treat mail as unauthenticated and are much more likely to send it to spam or reject it. DMARC is required by Google and Yahoo for senders of 5,000 or more messages a day and is good practice for everyone.
