SMTP Checker - Verify Your Email Server Configuration
Check SMTP server settings instantly with our free SMTP checker online. Verify connections, validate configurations, and ensure your email server is properly configured.
Connection Status
Check if your SMTP server is reachable and accepting connections on the specified port
Authentication Validation
Verify SMTP authentication credentials and supported authentication mechanisms
SSL/TLS Security
Check SMTP server SSL/TLS support and certificate validity for secure email transmission
Port Accessibility
Verify that common SMTP ports (25, 465, 587) are accessible and properly configured
Server Response Time
Check SMTP server response times and identify potential timeout issues
SMTP Command Support
Validate which SMTP commands (EHLO, AUTH, MAIL FROM, etc.) are supported
Relay Configuration
Check if SMTP relay is properly configured and whether authentication is required
Error Diagnostics
Identify and explain SMTP errors with detailed diagnostic information
Enter Server Details
Input your SMTP server hostname, port, and authentication credentials in the checker form
Run SMTP Check
Click the check button to start validating your SMTP server configuration and connection
Review Results
Analyze detailed diagnostic results and recommendations to fix any identified issues
Connection Refused
The SMTP checker cannot connect to the server - port might be blocked or server is down
Solution: Verify firewall settings, check if the port is correct, ensure the server is running
Authentication Failed
SMTP checker detected invalid credentials or unsupported authentication method
Solution: Verify username/password, check if app-specific password is required, confirm auth method
Relay Access Denied
The SMTP server is refusing to relay messages - authentication or IP restrictions may apply
Solution: Enable authentication, add IP to whitelist, check relay permissions
SSL/TLS Errors
SMTP checker found issues with SSL/TLS certificate or encryption protocol
Solution: Update SSL certificate, check security settings, try different encryption method
Gmail
Check Gmail SMTP
smtp.gmail.comPort: 587Office 365
Check O365 SMTP
smtp.office365.comPort: 587Amazon SES
Check SES SMTP
email-smtp.region.amazonaws.comPort: 587SendGrid
Check SendGrid SMTP
smtp.sendgrid.netPort: 587An SMTP checker online is an essential tool for anyone managing email infrastructure. Instead of manually testing connections or debugging cryptic errors, an SMTP checker automates the verification process and provides instant feedback on your email server configuration.
For Developers
- Check SMTP configuration before deploying applications
- Debug email delivery issues in development and production
- Validate SMTP credentials and authentication mechanisms
- Test different SMTP ports and security settings
For System Admins
- Monitor SMTP server health and availability
- Verify mail server configuration changes
- Troubleshoot connectivity and relay issues
- Ensure proper SSL/TLS certificate configuration
Check Your SMTP Server Now
Use our free SMTP checker to verify your email server configuration. Get instant results with detailed diagnostics and recommendations.
Start SMTP Check