mx record lookup email validation
MX record lookup email validation
Check whether a domain can receive mail before you accept the address.
MX lookup is the fastest domain-level signal.
It helps reject obviously broken domains early.
It pairs well with disposable and role-based checks.
dig MX example.com
nslookup -type=mx example.comWhat MX records tell you
MX records show where inbound mail for a domain should be delivered.
When lookup can still fail
Temporary DNS issues, misconfigured resolvers, or domains with fallback behavior can affect the result.
How MX lookup fits into the chain
MX checks are the first deliverability gate after syntax validation. If a domain cannot publish mail exchanger records, you already have a strong reason to reject or flag the address before spending time on deeper probes.
Operational tradeoff
MX lookup is inexpensive and fast, but it does not prove mailbox ownership. The best implementation treats it as a domain health signal and combines it with disposable-domain checks, score thresholds, and a clear user message.
FAQ
How do I use this page?
Use it as a quickstart reference and link it from your docs, onboarding flow, or marketing page.
What should I do next?
Create an account, try the demo, and move the integration into your backend with a real API key.
Should I block missing MX?
Usually yes for consumer signup flows, unless you intentionally support edge cases like custom routing.
Does MX guarantee inbox delivery?
No. It only indicates where mail should be delivered; the mailbox can still be unreachable or rejected later.