GET /mx/{domain}

MX API

See where a domain routes its mail.

Try it

Example response/mx/gmail.com
{
  "domain": "gmail.com",
  
    
      "priority": 5,
      "host": "gmail-smtp-in.l.google.com"
    },
    
      "priority": 10,
      "host": "alt1.gmail-smtp-in.l.google.com"
    }
  ]
}

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What comes back.

mx

Priority and host. A priority-0 host of . is null MX (accepts no mail); [] means no MX records.

1

Pass a domain

Hosts come back sorted the way mailers try them.

2

Read the distinction

An empty list means no MX. A host of . explicitly means no mail.

3

Fresh on lookup

Records refresh when their DNS lifetime expires.

Make your first request.

One key works across the APIs. Copy a request in your language and get JSON back.

curl "https://api.parseapi.com/mx/gmail.com" \
  -H "X-API-Key: YOUR_API_KEY" \
  -H "Parse-Version: 2.0.0"
// Example response · 200
{
  "domain": "gmail.com",
  "mx": [
    {
      "priority": 5,
      "host": "gmail-smtp-in.l.google.com"
    },
    {
      "priority": 10,
      "host": "alt1.gmail-smtp-in.l.google.com"
    },
    // ... 3 more
  ]
}

API referenceSDKsKeys and authentication

Every response field

Response fields

domainstring
Hostname checked
mxarray
Priority and host. A priority-0 host of . is null MX (accepts no mail); [] means no MX records.

QUESTIONS

What is a null MX?
A single record with priority 0 and host ".". The domain explicitly says it accepts no mail. We preserve that record in the mx array.
Does an empty list mean mail cannot be delivered?
No. An empty mx array means no MX records were found. SMTP can fall back to the domain A or AAAA address. The email API checks that route; mailbox verification is a separate question.
What comes back?
Hosts and priority, sorted the way mailers try them. Empty mx means the domain has no mail exchanger.
How fresh is it?
Lookups share the DNS API's freshness rules. Cached answers expire with their DNS lifetime, capped at one hour. Failed refreshes return an error instead of an old answer.
Does empty MX mean the domain is free?
No. Empty mx is mail routing only. Availability is GET /domain/{domain}.
Does an empty list prove the domain rejects mail?
No. Mail delivery can fall back to an A or AAAA record when MX records are absent. Use /email with deep to check a specific mailbox.

See the mail servers on any domain with the MX lookup.