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Querying MX records in real time…
MX Record Checker — Free MX Record Lookup
Instantly look up and validate the MX records for any domain. Verify mail server hostnames, priority values, TTL, IP resolution, and PTR records — free, real-time, no signup required. Checks mail server hostnames · priority values · IP resolution · PTR records · TTL · SPF context -> no signup required
How to Use the MX Record Checker
1
Enter any domain name (e.g.
example.com) in the input field above -> no need to include https:// or www.2
Click Check MX Records — all DNS queries run server-side in parallel using Google's public DNS resolver. Results appear on the same page, always fresh.
3
Review each mail server hostname, its priority, resolved IPs, PTR records, TTL, and the overall verdict with recommendations for improving your configuration.
Understanding MX Record Fields
| Field | What it means | Example |
|---|---|---|
| Priority | Lower number = higher priority. Mail is delivered to the lowest-priority server first. Equal-priority servers share traffic equally. | 10 |
| Mail Server | The hostname of the mail server that accepts incoming email. Must resolve to an A or AAAA record. | mail.example.com |
| IP Address | The IPv4 or IPv6 address the mail server hostname resolves to. A blank IP means the hostname has no A record -> a misconfiguration preventing delivery. | 142.250.10.26 |
| PTR Record | Reverse DNS for the mail server IP. Many receiving servers verify that the PTR matches the MX hostname. A missing or mismatched PTR can cause mail to be flagged as spam. | mail.example.com |
| TTL | Time To Live -> how long (in seconds) DNS resolvers cache this record before re-querying your authoritative nameserver. | 3600 |
Understanding Your Results
| Result | What it means | What to do |
|---|---|---|
| Valid | Two or more MX records found with different priorities. Your domain can receive email and has failover configured. | No action needed. Monitor periodically to ensure records stay correct. |
| Warning | Only one MX record found, or a hostname could not be resolved. Email may still arrive but there is no failover. | Add a secondary MX record with a higher priority number (e.g. 20) pointing to a backup server. |
| No Records | No MX records exist. All email sent to this domain will bounce immediately. | Add MX records via your DNS provider pointing to your mail provider (e.g. Google Workspace, Microsoft 365). |
| Priority badge | Green = primary (lowest number). Blue = secondary. Yellow = backup or fallback. | Ensure your primary server has the lowest number and backups have progressively higher values. |
| TTL value | How long DNS resolvers cache this record. High TTL means changes take longer to propagate worldwide. | Lower TTL to 300-600s before planned changes. Restore to 3600s+ afterward. |
What Is an MX Record?
An MX (Mail Exchanger) record is a DNS record that specifies which mail servers are responsible for receiving email on behalf of a domain. Without a valid MX record, email sent to your domain will bounce immediately with a delivery error.
Each MX record contains two key values: the hostname of the mail server and a priority number that determines which server is tried first. Lower priority numbers take precedence -> a server with priority 10 is tried before one with priority 20.
Why MX Records Matter for Email Security
Email Delivery
Without a valid MX record, email sent to your domain bounces immediately. Senders receive a permanent delivery failure error.
Redundancy
Multiple MX records with different priorities ensure email is delivered even if the primary server is offline. Sending servers automatically fail over to the next record.
Works with DMARC
MX records handle inbound delivery. DMARC, SPF, and DKIM protect your domain from outbound spoofing. Both are essential for a complete email security setup.
Propagation & TTL
MX record changes can take 1–48 hours to propagate worldwide. Lower your TTL before planned migrations to reduce the propagation window and minimise disruption.
Monitor Your MX Records in Real Time
