SMTP Finder: Find SMTP Server for Any Domain
Discover SMTP servers, ports, and email configuration settings to send emails correctly and troubleshoot deliverability issues.
Results
- Free SMTP lookup
- Instant results
- No signup required
What does this SMTP finder tool do?
Identify SMTP servers, email infrastructure, and configuration settings for any domain.
SMTP server discovery
Find the outgoing mail server (SMTP host) used by the domain.
Port detection
Identify common SMTP ports (25, 465, 587) and supported protocols.
Mail provider identification
Detect if the domain uses Google Workspace, Microsoft 365, or custom servers.
DNS & MX analysis
Analyze MX records to infer email routing and SMTP configuration.
Configuration insights
Understand how the domain is set up for sending emails.
Troubleshooting support
Help diagnose sending issues and misconfigurations quickly.
Common SMTP Server Examples
Here are standard SMTP configurations used by popular email providers.
Gmail SMTP
smtp.gmail.com (port 587)
Microsoft 365 SMTP
smtp.office365.com (port 587)
Yahoo SMTP
smtp.mail.yahoo.com (port 465)
Custom domain SMTP
smtp.yourdomain.com
Secure SMTP (SSL)
smtp.example.com (port 465)
TLS SMTP (recommended)
smtp.example.com (port 587)
How SMTP Works and Why It Matters
SMTP (Simple Mail Transfer Protocol) is the standard used to send emails from clients to servers and between servers.
When you send an email, your system connects to an SMTP server, authenticates the sender, and transmits the message to the receiving mail server.
Correct SMTP configuration ensures reliable delivery, while incorrect settings can cause failures or delays..
SMTP process includes:
Example:
mailX Related Email Authentication Tools
Check, validate, and improve the technical setup behind your email sending and deliverability.
Common SMTP Issues This Tool Detects
Wrong SMTP server
Incorrect host prevents sending.
Incorrect port
Connection fails due to wrong port selection.
Missing authentication
Server requires credentials but none provided.
Blocked port
Firewall or ISP blocks SMTP traffic.
No encryption
Security and deliverability issues occur.
Provider misconfiguration
Incorrect setup for the email provider.
SMTP, Email Configuration & Deliverability Guides
What Is SMTP and How It Works?
SMTP is the protocol that email servers use to send, relay, and deliver messages across the internet.
How to Fix SMTP Errors?
SMTP errors are response codes that tell you exactly what went wrong when an email fails to deliver.
Email Deliverability: The Complete Guide to Reaching the Inbox (2026)
Email deliverability refers to the ability of your emails to reach your recipient’s primary inbox rather than being filtered into spam...
Free SMTP Finder to Discover Email Server Settings
Use this SMTP finder to identify the SMTP server for a domain, discover email sending configuration, and troubleshoot email delivery issues.
SMTP is the protocol used to send emails between systems. If your SMTP configuration is incorrect, emails may fail to send, be delayed, or impact deliverability.
This tool helps you find SMTP hostnames, ports, and providers using DNS and MX record analysis.
SMTP Server Results
SMTP Server
Detected SMTP host for the domain
Ports
Available ports and recommended configuration
Issues & Fixes
Detected configuration issues & recommended fixes
Fix Your Email Deliverability with an Expert
Get a personalized audit of your SMTP setup, authentication, and email infrastructure. Identify what’s impacting your email sending and get clear, actionable fixes in a 30-minute session.