How to use it
- 1
Enter a domain without protocol.
- 2
Run the MX check.
- 3
Review MX count, priorities, and mail host address coverage.
What the tool can do
- Checks MX records and sortable priority values.
- Detects null MX as an explicit no-inbound-mail signal.
- Checks A/AAAA coverage for each MX host.
Common use cases
- Check a domain before corporate email setup.
- Find MX hosts without address records.
- Distinguish missing MX from intentional null MX.
How it works inside
The check is DNS-level only and does not perform SMTP transactions.
MX host addresses are checked through A/AAAA lookup without connecting to the mail server.
Questions and answers
Is one MX bad?
Not necessarily. One managed provider is enough for many domains; host reachability and SPF/DKIM/DMARC alignment matter more.
Does the MX checker test SMTP?
No. It checks DNS MX and host addressing; SMTP/TLS validation belongs to a separate network tool.