What is an MX record?

An MX (Mail Exchange) record tells sending mail servers which hosts accept email for a domain. Each record has a priority value and a hostname. Without an MX record, a domain generally cannot receive email reliably.

What does the MX priority number mean?

It sets the order servers are tried, lowest first. A record at priority 10 is preferred over one at priority 20, and the higher number acts as a fallback. Records sharing the same priority are used interchangeably, which spreads load.

Can an MX record point to an IP address?

No. The MX target must be a hostname that resolves to an A or AAAA record. Pointing it at a raw IP address, or at a CNAME, breaks delivery for senders that follow the specification strictly.

What happens if a domain has no MX record?

Senders fall back to the domain A record and attempt delivery there. That usually means mail arrives at a web server that is not running a mail service, so it bounces or disappears. Always publish explicit MX records.

How long do MX record changes take to apply?

As long as the TTL on the old record allows, since sending servers cache the previous answer. Lower the TTL a day before switching mail providers so the cutover happens in minutes rather than hours.

Do MX records stop spoofing of my domain?

No. MX records only control where incoming mail is delivered. Preventing others from sending as your domain requires SPF, DKIM and DMARC records, which this tool can also check.

MX Record Lookup

About MX Record Lookup

MX Record Lookup shows which mail servers accept email for a domain, and in what order. Each MX record carries a priority number, and the lower number wins: a record at priority 1 is tried before one at priority 10. Additional records at higher numbers act as backups, used only when the preferred servers do not answer. Equal priorities are treated as a pool and load balanced. If a domain has no MX record at all, senders fall back to its A record, which is rarely what anyone intends and is a common cause of mail silently going to a web server. The MX target must be a hostname that itself resolves to an address, never an IP address written directly and never a CNAME, since both break the lookup for strict senders. MX records only say where mail is accepted; they say nothing about who is allowed to send on your behalf. That is the job of SPF Record Checker and DMARC Record Checker, which are worth checking together whenever you change mail providers.

DNS resolution happens in multiple stages. When you type a domain name, your browser first checks its own cache, then the OS resolver cache, then queries your configured DNS resolver (usually your ISP or a public resolver like 8.8.8.8 or 1.1.1.1). If none have the record cached, the resolver performs a recursive query: it asks the root name servers for the TLD servers (.com, .net, etc.), then asks the TLD servers for the authoritative name servers of the specific domain, and finally asks the authoritative servers for the actual record. This entire process typically completes in under 100ms. DNS-over-HTTPS (DoH) encrypts DNS queries in HTTPS traffic, preventing ISPs and network observers from seeing which domains you query. It was standardized in RFC 8484 in 2018 and is now supported by all major browsers. Google and Cloudflare both operate free public DoH endpoints (dns.google and cloudflare-dns.com). TXT records have become a critical security mechanism: SPF (Sender Policy Framework) records specify which servers are allowed to send email for a domain, DKIM (DomainKeys Identified Mail) records provide public keys for verifying email signatures, and DMARC records tell receiving mail servers what to do when SPF or DKIM checks fail. Checking these records is the first step in diagnosing email deliverability problems.

How to use MX Record Lookup

Enter a domain name (e.g. example.com, without http://).
Select a record type (A, AAAA, MX, TXT, CNAME, NS, SOA, CAA, SRV, PTR) or an email policy check (DMARC, SPF, DKIM).
Click Lookup to see live DNS records, then copy all results with one click.

Frequently Asked Questions

What is an MX record?: An MX (Mail Exchange) record tells sending mail servers which hosts accept email for a domain. Each record has a priority value and a hostname. Without an MX record, a domain generally cannot receive email reliably.
What does the MX priority number mean?: It sets the order servers are tried, lowest first. A record at priority 10 is preferred over one at priority 20, and the higher number acts as a fallback. Records sharing the same priority are used interchangeably, which spreads load.
Can an MX record point to an IP address?: No. The MX target must be a hostname that resolves to an A or AAAA record. Pointing it at a raw IP address, or at a CNAME, breaks delivery for senders that follow the specification strictly.
What happens if a domain has no MX record?: Senders fall back to the domain A record and attempt delivery there. That usually means mail arrives at a web server that is not running a mail service, so it bounces or disappears. Always publish explicit MX records.
How long do MX record changes take to apply?: As long as the TTL on the old record allows, since sending servers cache the previous answer. Lower the TTL a day before switching mail providers so the cutover happens in minutes rather than hours.
Do MX records stop spoofing of my domain?: No. MX records only control where incoming mail is delivered. Preventing others from sending as your domain requires SPF, DKIM and DMARC records, which this tool can also check.

MX Record Lookup

About MX Record Lookup

How to use MX Record Lookup

Frequently Asked Questions

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