SMTP Test Tool

Test your connection to Sendgrid, Mailgun, Amazon SES, or any SMTP server. See the exact SMTP "conversation" to help you troubleshoot email issues. FAQ.

Need a different SMTP service? Here's my technical review of popular SMTP services.

SMTP Server

Sendgrid Mailgun SMTP2GO sendinblue JangoSMTP GMass

Port

25 2525 465 587

Security

Username

Password

From email address

To email address

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