Professional SMTP Server Testing Tool
Test and validate your SMTP server configuration instantly with our comprehensive, secure, and free online SMTP testing tool. Verify email delivery, troubleshoot authentication issues, and ensure your mail server is working perfectly. Supports all major email providers including Gmail, Outlook, SendGrid, Mailgun, and custom SMTP servers.
Real-time SMTP Testing
Watch your SMTP connection, authentication, and email delivery in real-time with detailed progress tracking and instant feedback on every step.
Secure SMTP Testing
Your SMTP credentials are processed securely and never stored. All tests run with enterprise-grade security and privacy protection.
Advanced SMTP Diagnostics
Get comprehensive SMTP logs with timing data, error analysis, server responses, and detailed troubleshooting information for debugging email issues.
SMTP Server Configuration
Configure your email server settings and test SMTP connectivity in real-time
Ready to Test
Configure your SMTP settings and click "Test SMTP Connection" to begin.
Supported SMTP Providers & Email Services
Test any SMTP server configuration with our comprehensive provider support
SMTP Testing Quick Start Guide
- • Choose your email provider preset or configure custom SMTP settings
- • Enable SMTP authentication for Gmail, Outlook, and most modern email services
- • Use STARTTLS encryption for secure email transmission (recommended)
- • Monitor real-time logs to troubleshoot connection and delivery issues
- • Test both authentication and email delivery in one comprehensive check
Frequently Asked Questions About SMTP Testing
What is SMTP and why do I need to test it?
SMTP (Simple Mail Transfer Protocol) is the standard protocol for sending emails. Testing your SMTP configuration ensures your email server can successfully send emails, authenticate properly, and handle various email scenarios without issues.
Is it safe to test my SMTP credentials here?
Yes, absolutely. Your SMTP credentials are processed securely and are never stored on our servers. All testing happens in real-time and your sensitive information is discarded immediately after the test completes.
Which email providers are supported?
We support all major email providers including Gmail, Outlook/Hotmail, Yahoo, SendGrid, Mailgun, Amazon SES, Postmark, Mandrill, SparkPost, Mailjet, and any custom SMTP server configuration.
What information do I need to test my SMTP server?
You'll need your SMTP server hostname, port number, security settings (TLS/SSL), and if authentication is required, your username and password. Most email providers have these settings readily available in their documentation.
Why am I getting authentication errors?
Authentication errors typically occur due to incorrect credentials, disabled SMTP access, or security settings. For Gmail, you may need to use App Passwords instead of your regular password. Check your email provider's SMTP documentation for specific requirements.
Can I test SMTP servers behind firewalls?
Our tool can test any publicly accessible SMTP server. If your SMTP server is behind a firewall or on a private network, you'll need to ensure the server is accessible from the internet or use our tool from within your network.
SMTP Guides & Documentation
Learn SMTP configuration, troubleshooting, and best practices