SMTP Test
Open an SMTP conversation, capture the greeting banner and enumerate advertised ESMTP capabilities.
Enter a value above and run the check to see results here.
How it works
Open an SMTP conversation, capture the greeting banner and enumerate advertised ESMTP capabilities.
Frequently asked questions
Is the SMTP Test tool free to use?+
Yes. The SMTP Test runs directly in NetInsight with no signup required. Free-tier usage is rate limited to keep the service fast for everyone.
Are my queries logged?+
Diagnostic inputs are processed to produce your result and are not sold or shared. See our Privacy Policy for full detail on retention.
How accurate are the SMTP Test results?+
Results are fetched live from authoritative sources each time you run a check, so they reflect the current state rather than a cached snapshot.