Check and diagnose SMTP server issues with our Online SMTP Server Test. Ensure email deliverability, authentication, and connectivity with real-time analysis.

Ensure your SMTP server is working correctly with our free online tester. Diagnose connection issues, authentication errors, and configuration problems in seconds.

Why Use Our SMTP Server Test Tool?

✅ Quick & Free – No installation or signup required.
✅ Real-Time Diagnostics – Test SMTP ports (25, 465, 587) and TLS/SSL.
✅ Detailed Reports – Identify errors like blocked ports or incorrect credentials.
✅ Developer-Friendly – Perfect for admins, DevOps, and IT teams.

How to Test Your SMTP Server:

1. Enter Server Details – SMTP host, port, username, and password.
2. Run Test – Check connectivity, authentication, and email sending.
3. Get Results – Fix issues based on error feedback.

Common SMTP Issues Detected:

🔴 Connection Refused – Firewall/port blocking.
🔴 Authentication Failed – Incorrect login details.
🔴 TLS/SSL Errors – Certificate misconfigurations.
🔴 Slow Response – Network or DNS problems.

Who Needs This Tool?

✔ System Admins – Validate server setups.
✔ Developers – Debug email-sending apps.
✔ Businesses – Ensure transactional emails work.
✔ IT Support – Troubleshoot client email issues.

FAQs

Q: Is this tool secure for testing SMTP credentials?
A: Yes, we don’t store your data—tests run in real-time.

Q: What ports does the SMTP tester support?
A: Standard ports (25, 465, 587) and custom ports.

Q: Can I test without authentication?
A: Yes, but some servers require login for full diagnostics.

Test your SMTP server now—fix email delivery issues in minutes!