Free Tools /Marketing
Email Deliverability Checker (MX, SPF, DMARC)
Check whether an address or domain can receive email, and whether a sending domain publishes SPF and DMARC, before you send.
- Free, no signup
- Public DNS only
- Nothing stored
Reads public DNS only. Nothing is stored.
Who uses it, and for what
Paste each prospect address and drop the ones whose domain has no mail server.
Check your own sending domain for SPF and a DMARC policy.
Spot disposable and free webmail addresses before they reach your sales team.
How this tool works
Public DNS only
The checker reads the domain's public DNS records: MX (where its email is delivered), SPF (which servers may send for it) and DMARC (what receivers should do with mail that fails authentication). It never connects to a mail server and never tests whether a mailbox exists.
Address quality
For a full address it also flags role addresses such as info@ or sales@, free webmail domains and common disposable domains, the three things that most often explain a cold email that goes unanswered or bounces.
Plain-English verdict
Each result says what it means and what to do next: send, find a named contact first, or fix your own domain's authentication before your next campaign.
Guide
What should a healthy sending domain show?
At least one MX record, one SPF record that ends with -all or ~all, and a DMARC record. Start DMARC with p=none to collect reports, then move to quarantine or reject once every service that sends for you is authenticated.
What should I do with a role address?
Look for a named address on the company website (team or contact page) on the same domain. If there is none, keep the role address and write a message that is easy to forward internally.
Frequently asked questions
Does this tool verify that a mailbox exists?
No. Confirming a single mailbox requires talking to the recipient's mail server, which many servers block or answer misleadingly, and which can hurt your sending reputation. This tool checks what the domain publishes in DNS, which is enough to catch domains that cannot receive email at all.
What does "no MX record" mean?
The domain publishes no mail server, so email sent to any address at that domain will normally bounce. Remove those addresses from your list before sending.
Why does SPF or DMARC matter for my own domain?
Receivers use SPF, DKIM and DMARC to decide whether a message really comes from your domain. Gmail and Yahoo require authentication from bulk senders, so a missing SPF or DMARC record on the domain you send from is one of the first things to fix when campaigns land in spam.
Why is DKIM not checked?
DKIM keys are published under a selector name chosen by each email provider (for example google._domainkey). Without the selector, a DNS lookup cannot find the key reliably, so the tool does not guess. Your email provider's admin panel shows whether DKIM is on.
Is a role address like info@ bad?
Not invalid, but it is usually read by whoever is on duty and filtered more aggressively. For outreach, a named address on the company's own domain gets a better chance of reaching the decision-maker.
Do you store the addresses I check?
No. The address is used for one set of DNS lookups and is not saved, logged in a database or used for marketing.
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