Find mail servers for any domain. Detect email providers, verify reverse DNS, check priority routing, and identify misconfigurations that affect email delivery.
MX (Mail Exchange) records are DNS entries that tell sending mail servers where to deliver email for a domain. When someone emails [email protected], the sending server queries the MX records for example.com to find which mail servers should receive the message.
Each MX record has two parts: a priority number and a hostname. Lower priority numbers are tried first. If the primary server is down, the sender retries with the next-priority server. This provides built-in redundancy for email delivery.
This tool automatically identifies the email provider behind a domain's MX records. Knowing which provider handles a domain's email is useful for troubleshooting delivery issues, understanding a competitor's email stack, or verifying a migration was successful.
*.google.com*.protection.outlook.com*.pphosted.com*.mimecast.com*.barracudanetworks.com*.zoho.comThe tool detects 30+ providers including Amazon SES, SendGrid, Mailgun, Postmark, ProtonMail, Fastmail, Apple iCloud, and more.
For each MX server, this tool resolves the IP address and performs a PTR (reverse DNS) lookup. Forward-confirmed reverse DNS (FCrDNS) means the PTR hostname resolves back to the same IP — a key requirement for email deliverability.
Major email providers like Gmail, Outlook, and Yahoo check PTR records as part of their spam filtering. A mismatch between the sending hostname and its reverse DNS can cause emails to be rejected or sent to spam. If you see a PTR mismatch in your results, contact your hosting provider to set the correct PTR record.
MX records are just one part of email configuration. For a complete email health check, also verify your authentication records: