MX records checker
Look up the mail servers for any domain and check that each one is set up to receive email.
Every MX record
Listed by priority, lowest number first.
Whether each server resolves
We look up the IP addresses behind every mail server.
What to fix
If a record is missing or broken, you get the change to make.
What MX records do
MX (mail exchange) records tell other mail servers where to deliver email for your domain. When someone replies to your cold email, their server looks up your MX records to find your inbox.
If they’re missing or point at a server that’s gone, replies bounce. Some inbox providers also trust a domain less when it can’t receive mail.
How to use it
- 1
Enter your domain. Paste a domain, a website address or an email address. We’ll work out the domain.
- 2
Read the results. Each mail server is listed with its priority and whether it resolves.
- 3
Fix what’s flagged. Make the change at your DNS provider, then run the check again.
Questions about MX records
What does MX priority mean?
Mail goes to the server with the lowest number first. Higher numbers are backups that are used when the first server doesn’t answer.
How many MX records should I have?
Use exactly what your email provider tells you to add. Google Workspace now uses a single record (smtp.google.com), older setups list five aspmx servers, and Microsoft 365 uses one record ending in mail.protection.outlook.com.
How long do MX changes take to work?
Usually a few minutes, but up to 48 hours depending on your DNS provider and the old record’s TTL.
Do MX records matter if I only send cold email?
Yes. Without them, replies to your campaigns can’t reach you, and some receivers treat a domain that can’t receive mail as less trustworthy.
Why does my result show a CNAME warning?
An MX record should point at a hostname with its own A record. If it points at a CNAME, some mail servers refuse to deliver. Point the MX record at the final hostname instead.
Setup checks out? Start sending.
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