Free tool

Free MX record checker

Use this MX record checker to confirm a domain can receive replies and see which mail provider handles it, such as Google Workspace or Microsoft 365.

This checks MX record for one domain. For a real launch verdict, run every domain, inbox, and tracking domain through the full QA pass.

Runs live in your browser via public DNS. Nothing is stored.

Keep a reply-routing mistake from delaying a client launch

A clean MX result gives the agency a defensible next step: name the provider that should receive replies, assign the routing fix if it is wrong, then preserve an inbound test with the client launch record.

How to read the result

The checker lists the MX hosts and detects the provider from common host patterns. If there is no MX record, the domain cannot receive mail, which becomes visible the moment a prospect replies or your team tests the inbox.

MX is one of the first checks in a cold email launch QA pass. OutboundQA verifies it across every inbox in the workspace alongside SPF, DKIM, DMARC, tracking SSL, and blacklist checks before a campaign goes live.

How to check Google Workspace MX records

Run the root domain through the checker and compare the public answer with the Google Workspace setup that should receive replies. A current setup uses smtp.google.com at priority 1. Older working setups can still use Google's legacy aspmx records.

Current setup: MX 1 smtp.google.com.
Legacy setup: Supported hosts beginning with aspmx and alt
Launch blocker: No MX record, a null MX record, or hosts left behind by a previous provider

1. Check the root domain. Enter the domain without https:// or www.
2. Match the expected provider. Remove stale MX records instead of leaving Google and a previous provider active together.
3. Verify the private setup. Confirm the domain is verified and Gmail is active in Google Admin.
4. Test a real reply path. Send an inbound message from an unrelated provider and confirm it reaches the monitored inbox.

The lookup reads public DNS only. It cannot see a suspended account, missing mailbox license, disabled Gmail service, routing rule, or whether anyone monitors the inbox. Compare the result with Google's current MX instructions, then use the MX routing guide for legacy records, Microsoft 365, null MX, and migration checks.

What this check does not catch

A passing MX record lookup is useful, but it is not launch signoff. Cold email campaigns still fail when adjacent records, tracking domains, or inbox-level settings are broken.

SPF records

DKIM selectors

DMARC policy

tracking-domain SSL

blacklist status

Google and Yahoo sender requirements

Setup guides for this check

Read the setup notes behind this result, then verify the neighboring records before launch.

MX records and mail routing

How MX records route replies and bounces, provider records for Google and Microsoft, and common mistakes.

Google and Yahoo bulk sender requirements

SPF, DKIM, DMARC, one-click unsubscribe, and the spam-rate thresholds bulk senders must meet.

Domain warmup and safe sending volume

Why new domains are high risk, ramp schedules, per-inbox daily limits, and domain age.

Need to check a full outbound workspace?

OutboundQA checks every domain, inbox, and tracking domain in the workspace, then gives you a shareable report with a Ready, Needs Fix, or Do Not Launch verdict.

Run a free workspace check View a sample report

Cold email launch checks to run next

Use this result as one checkpoint in the launch flow. Then verify the neighboring records and run the combined domain check before the outbound launch goes live.

SPF Checker

Look up a domain's SPF record and count its DNS lookups against the limit of 10.

DMARC Checker

Look up a domain's DMARC record and read its policy in plain English.

DKIM Checker

Look up a domain's DKIM selector and confirm the public key exists.

Auth Checker

Run SPF, DKIM, and DMARC together for a sending domain before launch.

Blacklist Checker

Check a domain and sampled mail server IPs against domain and email blocklists.

Reputation Checker

Check observable cold email reputation risks across age, blacklist, authentication, MX, and HTTPS signals.

Deliverability Checker

Check observable cold email infrastructure readiness across MX, SPF, DKIM, DMARC, blacklist, age, tracking-domain, and SMTP egress identity signals.

Receiver Checker

Check observable Gmail, Yahoo, and Microsoft sender requirements from public DNS and optional pasted message headers.

Recipient Preflight

Paste emails or domains and classify MX provider, free inboxes, security gateways, SPF, DMARC, and receive-mail readiness.

Tracking Checker

Check a branded cold email tracking domain for CNAME setup, DNS resolution, HTTPS, and redirect handoff.

MTA-STS Checker

Check MTA-STS and TLS-RPT records for inbound mail security posture before a cold email launch.

PTR/rDNS Checker

Check a custom SMTP egress IP for PTR, reverse DNS, and forward-confirmed rDNS before launch.

Launch Checklist

Generate a pre-launch QA checklist for domains, inboxes, authentication, tracking domains, blacklist checks, and signoff.

Domain Checker

Run MX, SPF, and DMARC in one pass for a quick readiness verdict on a sending domain.

Burn History

Check whether a domain has already sent cold email, carried a tracking hostname, or picked up a listing, before you buy it.

Sample Launch QA Report

See the report founders, teams, and agencies can share after the full QA pass.

Email Deliverability Tool

See how one-off checks turn into pre-launch QA for full cold email workspaces.

Questions

MX (Mail Exchange) records tell other servers where to deliver mail for your domain. No MX record means the domain cannot receive mail, which is a launch blocker for any inbox you expect replies on.

Run the domain through this checker and confirm public DNS returns smtp.google.com at priority 1 for a current setup, or the supported legacy aspmx host set for an older setup. Then confirm Gmail is active in Google Admin and send a real inbound test. DNS alone cannot verify the mailbox.

No. Google says working legacy aspmx records remain supported. Keep one documented Google record scheme, remove stale records from other providers, and test an inbound message before launch.

The detected provider tells you where replies should be delivered and helps expose migration mistakes. If public MX points to Google but the active inboxes live in Microsoft 365, replies can reach the wrong system. Provider detection does not predict inbox placement.

This tool checks MX (receiving) and detects the provider. A full launch check also covers SPF, DKIM, DMARC, tracking SSL, blacklist, and domain age. That is what OutboundQA runs.

Hold the affected launch, confirm which provider should receive replies, remove stale routing records only with the DNS owner, and send a real inbound test after the change. Keep the rerun with the client launch evidence because DNS alone cannot prove the mailbox is active.

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