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SMTP Tester

Connect to any SMTP server with your host, port and credentials, send a test email, and inspect the full SMTP session log — STARTTLS, SSL/TLS or plain. Great for debugging deliverability and auth.

Connection

Recommended port:

Port 2525 doesn't match STARTTLS. Most servers expect port 587.

Message

SMTP Session Log

Fill in the connection details and click "Send Test" to begin.

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