TCP connection
Can your client reach the SMTP host on the selected port?
01 free tool
SMTP test — verify connection, authentication, and TLS.
Confirm your SMTP hostname, port, username, and encryption settings before sending production mail. Use after configuring SMTP-X or any SMTP provider.
What does the SMTP test check?
TLS & auth
STARTTLS or implicit SSL negotiation and LOGIN/PLAIN authentication.
Ready to send
After a successful test, send a real message through the Mail Tester.