MX Lookup API

About the MX Lookup API

Pass any domain name to run a live DNS lookup for its mail configuration. The response returns the queried domain and an array of MX entries, showing each mail exchange server hostname paired with its priority routing integer.

What people use it for

Signup Email Validation

To stop fake signups, authentication workflows check MX records to confirm the registrant's email domain can actually accept incoming messages.

Domain Migration Auditing

DevOps engineers track exchange hostnames and priority numbers before and after DNS changes to verify mail traffic directs to new servers.

Cold Outreach Deliverability

Sales outreach software verifies that recipient domains have active mail servers before scheduling outbound campaign sequences to protect sender reputation.

Mail Provider Detection

Identify whether a prospect uses Google Workspace, Microsoft 365, or self-hosted infrastructure by parsing the returned exchange server hostnames.

Ways to call it

One endpoint, many ways in — REST with JSON, XML, YAML and CSV, plus GraphQL and an MCP interface for AI agents.

JSON

Default REST response

XML

Markup format

YAML

Human-readable

CSV

Tabular export

Beta

GraphQL

Query language

New

MCP

For AI agents

How it compares

Side by side with the tools people weigh MX Lookup against — what each one is better at, in plain terms.

Request parameters — GET /v1/mxlookup

Sent in the query string. Premium parameters are accepted on every plan but only take effect on plans that include them. Anything not listed here is dropped rather than passed through.

Required

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curl "https://api.apiverve.com/v1/mxlookup?domain=yahoo.com" \
  -H "x-api-key: YOUR_API_KEY"

Authentication

Send your key in the x-api-key header. That is the only auth step — no token exchange, and no per-endpoint scope to configure.

Response — GET /v1/mxlookup

Every APIVerve endpoint returns the same three top-level keys, so one response handler covers your whole integration: status, error and data. Only data changes shape.

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{
  "status": "ok",
  "error": null,
  "data": {
    "domain": "yahoo.com",
    "mx": [
      {
        "priority": 1,
        "exchange": "mta7.am0.yahoodns.net"
      },
      {
        "priority": 1,
        "exchange": "mta6.am0.yahoodns.net"
      },
      {
        "priority": 1,
        "exchange": "mta5.am0.yahoodns.net"
      }
    ]
  }
}

Response fields

Paths are relative to data. Premium fields are absent rather than zeroed on plans that do not include them, so check for presence instead of comparing to 0.

Response headers

Every response carries your balance, so your own code always knows where it stands without polling anything. All four are exposed to browsers through CORS.

Errors

Read the HTTP status first, then error for the specific reason. The body names the parameter that has to change.

What a call costs — 10 credits per call

Credits are shared across every APIVerve API — one balance, one key, one bill. Failed requests never count against it, so a rejected input costs nothing.

Calls are what the credits buy at this API's rate — spend them here, on any of the other APIs, or across both. Nothing is reserved per endpoint.

Zero-code embed — one snippet, no backend

Drop an interactive MX Lookup form onto any page. The widget calls the API for you, so no key ever appears in your markup and there is nothing to deploy.

Changelog — MX Lookup API

Every change to this endpoint, newest first. Breaking changes ship as a new version and the previous one keeps serving — response fields are added, never removed or retyped in place, so an integration written against v1 keeps working.

Currently v1Data refreshed realtime