Professional SMTP Test Tool for Email Server Diagnostics

Comprehensive SMTP testing tool with advanced diagnostics, real-time monitoring, and detailed reporting. Test any SMTP server configuration with professional-grade accuracy.

Instant Testing
Test SMTP servers in seconds with our fast and efficient testing tool
Real-Time Logs
Watch SMTP commands and server responses in real-time terminal output
Secure Testing
All credentials are ephemeral and never stored on our servers
Professional-Grade SMTP Testing Features
Everything you need in an enterprise-level SMTP test tool

Multi-Protocol Support

Our SMTP test tool supports all authentication methods including PLAIN, LOGIN, CRAM-MD5, and more

SSL/TLS Testing

Test both SSL/TLS and STARTTLS connections with certificate validation and encryption verification

Detailed Diagnostics

Get comprehensive diagnostic reports with error analysis, suggestions, and performance metrics

Performance Monitoring

Track connection times, command latency, and overall SMTP server performance

Email Delivery Testing

Send actual test emails to verify end-to-end delivery and check inbox placement

Configuration Presets

Quick-start templates for Gmail, Office 365, SendGrid, Amazon SES, and other popular providers

How to Use the SMTP Test Tool
Complete guide to testing your SMTP server configuration

1Configure Connection Settings

Start by entering your SMTP server details in the test tool:

  • Server Host: Enter your SMTP server hostname (e.g., smtp.gmail.com)
  • Port: Select the appropriate port (587 for STARTTLS, 465 for SSL/TLS)
  • Security: Choose encryption method (Auto, SSL/TLS, STARTTLS, or None)

2Add Authentication Credentials

If your SMTP server requires authentication, provide your credentials:

  • Username: Your SMTP username (often your full email address)
  • Password: Your SMTP password or app-specific password
  • Note: Credentials are only used temporarily and never stored

3Run the Test and Analyze Results

Click the test button and watch the real-time output:

  • Monitor SMTP command execution in the terminal window
  • Review server responses and any error messages
  • Analyze diagnostic suggestions for fixing any issues
SMTP Test Tool Use Cases
Who benefits from using our SMTP testing tool

Web Developers

  • Test SMTP configuration in applications
  • Debug email sending functionality
  • Verify email server credentials
  • Test before production deployment

System Administrators

  • Monitor mail server health
  • Validate server configuration changes
  • Troubleshoot delivery issues
  • Verify SSL/TLS certificates

Email Marketers

  • Test email service providers
  • Verify SMTP relay services
  • Check deliverability settings
  • Monitor campaign infrastructure
Test Any SMTP Server
Our SMTP test tool works with all major email providers and custom servers

Gmail SMTP

Host: smtp.gmail.com

Port: 587

Office 365

Host: smtp.office365.com

Port: 587

Amazon SES

Host: email-smtp.region.amazonaws.com

Port: 587

SendGrid

Host: smtp.sendgrid.net

Port: 587

Mailgun

Host: smtp.mailgun.org

Port: 587

Postmark

Host: smtp.postmarkapp.com

Port: 587

Yahoo Mail

Host: smtp.mail.yahoo.com

Port: 587

Custom SMTP

Host: your-server.com

Port: 25/587/465

Start Testing Your SMTP Server

Use our professional SMTP test tool to diagnose email server issues, verify configurations, and ensure reliable email delivery.

Launch SMTP Test Tool