This professional and free-of-charge service allows you to test your SMTP connection, identify and fix possible sending issues in 3 different ways.
Check your SMTP connection and see the full SMTP session log to resolve any email-sending concerns. Check the connection to Amazon SES, SendGrid, Mailgun, Sendinblue, Google SMTP, Elastic Email, SMTP2GO, UniOne, or any other SMTP server.
“SMTP Test” for a quick check-up, “SMTP Proxy” for debugging specific SMTP sessions, or “SMTP Blackhole” for the most protected test.
Read them carefully, and do not hesitate to Contact Us if you need assistance
Sending numerous emails may sometimes be quite a tricky thing. Checking your SMTP server operation may help you prevent possible deliverability issues and ensure that all of your emails reach their recipients. Using the SMTP Debug Tool is also a great way to learn the inner workings of the SMTP protocol.
The Tool establishes an SMTP session based on the provided parameters and sends a free test email. After that, it shows you the entire log of the “conversation” between servers, so that you can check if everything has gone right or if any problems need to be fixed.
Non-logged-in users can specify values for all the required fields: “Email From” and “Email To” addresses, Host, Port number, Username, and Password. For other fields, placeholders will be used.
If you sign in, you will be able to specify your own “Subject”, “HTML Body”, and additional email header fields, so you can test the contents of the letter as well.
Please note that the maximum length of a header name is 75 bytes, and it should contain only ASCII symbols, while the header value should not exceed 4000 bytes and it can include any UTF-8 symbols.
After inserting all the necessary data and pressing the “Send” button, you will see the session status at the top of the page (above the form), which may be one of the following:
Yes, we guarantee you that this is absolutely safe as both your connection to our site and the SMTP session are encrypted, and we do not keep the session log or any of the information you enter. Also, you may change your password after completing the tests to keep the highest level of privacy. Plus, you may use the “SMTP Blackhole” Tool without entering your credentials for maximum security.
Our SMTP Debug Tool is entirely free of charge.
However, we are a responsible company that fully respects spam prevention policies. That’s why we put certain restrictions on the number of requests. For SMTP Test:
For SMTP Proxy tools:
We believe the SMTP Debug Tool is one of the most complete and comfortable web-based SMTP testing tools because of the following advantages:
Please ensure you’ve followed all the instructions and haven’t reached the hourly limits (mentioned above).
If everything looks correct, but the session still hasn’t started, feel free to request assistance via the form in the “Contact Us” section.