DNS MX Record Lookup: Find Mail Server Records

DNS MX records (Mail Exchanger records) specify which mail servers are responsible for receiving email on behalf of a domain. When someone sends you an email, their mail server queries the MX records of your domain to find where to deliver the message. Without correctly configured MX records, email delivery fails entirely.

How to Look Up MX Records

1. Enter the domain — Input the domain whose mail servers you want to find (e.g., gmail.com).
2. Select MX record type — Pick \"MX\" from the record type dropdown.
3. Run the lookup — Results appear showing each mail server hostname and its priority value.
4. Interpret priority — Lower numbers mean higher priority. Mail is delivered to the lowest-priority server first; higher numbers are fallback servers.

Example: Querying MX Records

# Using dig
dig example.com MX

# Using nslookup
nslookup -type=MX example.com

# Example output for a Google Workspace domain:
# example.com.   3600   IN   MX   1  aspmx.l.google.com.
# example.com.   3600   IN   MX   5  alt1.aspmx.l.google.com.
# example.com.   3600   IN   MX   10 alt2.aspmx.l.google.com.

Why Check MX Records?

• Fix email delivery failures — If email is bouncing or not arriving, incorrect MX records are a common cause.
• Verify email provider migration — After switching from one email provider to another (e.g., Outlook to Google Workspace), confirm the new MX records are live.
• Security checks — Unexpected MX records may indicate your domain has been compromised or misconfigured.
• Understand failover setup — Multiple MX records with different priorities provide redundancy for mail delivery.

Common MX Record Configurations

Google Workspace uses aspmx.l.google.com as the primary server. Microsoft 365 uses {tenant}.mail.protection.outlook.com. Proton Mail uses mail.protonmail.ch. Each provider gives you specific MX record values to add to your DNS zone.

MX Records and SPF / DKIM / DMARC

MX records tell the world where to send email. SPF, DKIM, and DMARC records (stored as TXT records) tell the world how to verify that email from your domain is legitimate. Together, these records prevent spam and spoofing. After setting up MX records, always verify your TXT records are correctly configured too.

Check MX records for any domain in seconds with the DNS Lookup tool — no terminal needed.