001DOMAIN
Enter a domain
Drop in any domain you want to inspect. No login, no account, nothing to install. A single domain is all the lookup needs to start.
Domain mail lookup
The Mail Domain Lookup That Shows a Domain's Whole Mail Setup.
Enter any domain to see the mail provider behind it, its MX records in priority order, and whether the domain accepts email. One snapshot of the whole mail setup. No signup.
Try:
Trusted by 500,000+ leading GTM teams of all sizes
From domain to mail setup
How the mail domain lookup works
Three steps, no login, no install. Enter a domain, let Verifox query its DNS, then read the mail setup, the provider, the MX routing, and whether the domain receives email.
002QUERY
Query the DNS records
Verifox queries the domain's DNS for its MX records, the same resolution step our verification engine runs first. The records come straight from the authoritative nameservers.
003READ
Read the mail routing
See the MX records in priority order, the provider that runs the mail, and whether the domain accepts mail at all. That is the deliverability signal a verification starts from.
What it shows
What a mail domain lookup reveals
A mail domain lookup is a read-only window into how a domain handles email. In one query you learn who runs the mail, how it routes, and whether the domain can accept it at all.
Provider
MXrecords read
Who runs the mail
The MX hosts name the provider behind a domain at a glance, Google Workspace, Microsoft 365, Proofpoint, or a self-hosted server, which is the single most useful thing a mail exchanger lookup tells you.
Routing
0–∞preference order
Routing and priority
Records return in preference order, lowest number first, so you can read the primary mail server and its fallbacks straight away and spot a missing or duplicated backup.
Deliverability
Step 1of deliverability
A deliverability signal
No MX record, or a broken one, means mail will bounce before it is ever sent. An MX lookup is step one of deliverability, then verifying the address confirms the mailbox itself.
Engine
1shared resolver
The same engine, free
This is the exact DNS resolution Verifox runs as the first stage of its verification engine, exposed here free. Pair it with SPF, DKIM, and DMARC checks for the full authentication picture.
The plain-English version
What a mail domain lookup actually does
A mail domain lookupstarts with a single domain and reads back its whole mail configuration. Under the hood it queries the domain's DNS for its MX records, the entries that decide where the domain's email is delivered, and then turns those raw records into the answer you actually came for: who runs this domain's mail, and is it set up to receive any. Every domain that can accept mail publishes at least one MX record, and each one names a mail server together with a priority number.
The provider falls straight out of those hostnames. Records pointing at aspmx.l.google.com mean Google Workspace, mail.protection.outlook.com means Microsoft 365, and a custom hostname usually means a self-hosted or niche provider, so a domain mail lookuptells you who hosts a domain's email without you decoding anything. The priority numbers reveal the routing: the lowest number is the primary mail server, the higher ones are fallbacks. And if the domain returns no MX record at all, that is the loudest signal of them all, mail sent to it has nowhere to land and will bounce. This is exactly the resolution our verification engine runs before it goes any further.
This page is the overview; the detail lives one click away. When you want to read every record literally, the MX records lookup lists each host and priority on its own, and the SPF, DKIM, and DMARC check reads the authentication records that decide whether your mail lands in the inbox or the spam folder. And here is the honest boundary: a mail domain lookup proves the domain can accept mail; it says nothing about whether a specific mailbox on it is real. So when you need to confirm an actual address is reachable, the free email checker runs the SMTP-level mailbox check. Wiring any of it into your own stack or an AI agent? The same engine is available through the REST API and a native MCP server, with pay-as-you-go pricing localized to your region on the pricing page.
How we stack up
Verifox vs other MX lookup tools
MXToolbox, DNSChecker, and Google Admin Toolbox all return MX records. Verifox names the provider in plain English, runs ad-free with no signup, and flows the lookup straight into a real mailbox verification that a standalone DNS tool cannot.
| Feature | Verifox | MXToolbox | DNSChecker | Google Toolbox |
|---|---|---|---|---|
| MX records in priority order | ||||
| Names the mail provider | Plain English | Hostnames | Hostnames | Hostnames |
| No ads, no signup wall | ||||
| Flows into mailbox verification | Built in | |||
| REST API for lookups | ||||
| MCP server for AI agents | ||||
| Bulk domain lookup | ||||
| Pricing model | Pay as you go | Subscription | Free | Free |
What teams are saying
Built for the teams that ship outbound
Growth leads, marketers, and engineers running real campaigns on real lists. Specific numbers, specific tools they switched from, and a verified email address on every byline.
90% lower bill, 0.4% bounces
We were paying ZeroBounce a four-figure monthly bill and still landing 3% bounces on cold campaigns. Switched the pipeline to Verifox, dropped to 0.4% bounces, and cut the bill by more than 90%.
Thomas G.GTM Lead, Stripe
Catch-all finally has a verdict
Other tools flag 30% of our B2B list as 'risky catch-all' and leave the call to us. Verifox returns a real verdict on those addresses, with a confidence score. We send more, we send safer.
Brittany K.GTM Lead, HubSpot
Reputation rebuilt in 6 weeks
We had a Gmail spam-folder problem after a bad list import. Verifox cleaned the list and the warmup ran on the same engine. Back in primary inbox in six weeks. One vendor, half the cost.
Dale M.GTM Lead, Slack
0.7% bounce on 50k
Ran a 50,000-address outbound list through Verifox before our quarterly campaign. Bounces landed at 0.7%, sender reputation didn't move, replies were up 22% over last quarter.
Erica K.GTM Lead, Discord
MCP in 10 minutes
Their MCP server let me wire email verification directly into our internal Claude agent in about ten minutes. Zero glue code. No other vendor in this space has thought about that workflow.
Greg L.GTM Lead, OpenAI
10k/min held under 400ms
Tested Verifox at 10,000 verifications per minute on a Tuesday morning. Latency held under 400ms median, no soft failures, no rate-limit walls. The vendor we benched throttled at 2,000/min.
Rini V.Product Manager, Vercel
Hygiene that doesn't break pipeline
Our SDRs were enriching from three tools and 14% of the emails were invalid before they hit the sequencer. Verifox sits in the pipeline now and the team stopped seeing 'undeliverable' replies the next week.
Jonathan A.GTM Lead, MongoDB
Bulk that actually ships
Bulk upload, sorted CSV back in twenty minutes, plug into our growth stack. The half-day list-hygiene project per cohort turned into something the marketing intern runs on autopilot.
Emma F.GTM Lead, Linear
Scores you can act on
Verifox returns a 0-100 confidence score per address, not just a label. We thresholded at 75 for the cold sequencer, 60 for nurture, and our deliverability team finally has a knob they can tune.
David H.GTM Lead, Snowflake
90% lower bill, 0.4% bounces
We were paying ZeroBounce a four-figure monthly bill and still landing 3% bounces on cold campaigns. Switched the pipeline to Verifox, dropped to 0.4% bounces, and cut the bill by more than 90%.
Thomas G.GTM Lead, Stripe
Reputation rebuilt in 6 weeks
We had a Gmail spam-folder problem after a bad list import. Verifox cleaned the list and the warmup ran on the same engine. Back in primary inbox in six weeks. One vendor, half the cost.
Dale M.GTM Lead, Slack
MCP in 10 minutes
Their MCP server let me wire email verification directly into our internal Claude agent in about ten minutes. Zero glue code. No other vendor in this space has thought about that workflow.
Greg L.GTM Lead, OpenAI
Hygiene that doesn't break pipeline
Our SDRs were enriching from three tools and 14% of the emails were invalid before they hit the sequencer. Verifox sits in the pipeline now and the team stopped seeing 'undeliverable' replies the next week.
Jonathan A.GTM Lead, MongoDB
Scores you can act on
Verifox returns a 0-100 confidence score per address, not just a label. We thresholded at 75 for the cold sequencer, 60 for nurture, and our deliverability team finally has a knob they can tune.
David H.GTM Lead, Snowflake
Catch-all finally has a verdict
Other tools flag 30% of our B2B list as 'risky catch-all' and leave the call to us. Verifox returns a real verdict on those addresses, with a confidence score. We send more, we send safer.
Brittany K.GTM Lead, HubSpot
0.7% bounce on 50k
Ran a 50,000-address outbound list through Verifox before our quarterly campaign. Bounces landed at 0.7%, sender reputation didn't move, replies were up 22% over last quarter.
Erica K.GTM Lead, Discord
10k/min held under 400ms
Tested Verifox at 10,000 verifications per minute on a Tuesday morning. Latency held under 400ms median, no soft failures, no rate-limit walls. The vendor we benched throttled at 2,000/min.
Rini V.Product Manager, Vercel
Bulk that actually ships
Bulk upload, sorted CSV back in twenty minutes, plug into our growth stack. The half-day list-hygiene project per cohort turned into something the marketing intern runs on autopilot.
Emma F.GTM Lead, Linear
90% lower bill, 0.4% bounces
We were paying ZeroBounce a four-figure monthly bill and still landing 3% bounces on cold campaigns. Switched the pipeline to Verifox, dropped to 0.4% bounces, and cut the bill by more than 90%.
Thomas G.GTM Lead, Stripe
0.7% bounce on 50k
Ran a 50,000-address outbound list through Verifox before our quarterly campaign. Bounces landed at 0.7%, sender reputation didn't move, replies were up 22% over last quarter.
Erica K.GTM Lead, Discord
Hygiene that doesn't break pipeline
Our SDRs were enriching from three tools and 14% of the emails were invalid before they hit the sequencer. Verifox sits in the pipeline now and the team stopped seeing 'undeliverable' replies the next week.
Jonathan A.GTM Lead, MongoDB
Catch-all finally has a verdict
Other tools flag 30% of our B2B list as 'risky catch-all' and leave the call to us. Verifox returns a real verdict on those addresses, with a confidence score. We send more, we send safer.
Brittany K.GTM Lead, HubSpot
MCP in 10 minutes
Their MCP server let me wire email verification directly into our internal Claude agent in about ten minutes. Zero glue code. No other vendor in this space has thought about that workflow.
Greg L.GTM Lead, OpenAI
Bulk that actually ships
Bulk upload, sorted CSV back in twenty minutes, plug into our growth stack. The half-day list-hygiene project per cohort turned into something the marketing intern runs on autopilot.
Emma F.GTM Lead, Linear
Reputation rebuilt in 6 weeks
We had a Gmail spam-folder problem after a bad list import. Verifox cleaned the list and the warmup ran on the same engine. Back in primary inbox in six weeks. One vendor, half the cost.
Dale M.GTM Lead, Slack
10k/min held under 400ms
Tested Verifox at 10,000 verifications per minute on a Tuesday morning. Latency held under 400ms median, no soft failures, no rate-limit walls. The vendor we benched throttled at 2,000/min.
Rini V.Product Manager, Vercel
Scores you can act on
Verifox returns a 0-100 confidence score per address, not just a label. We thresholded at 75 for the cold sequencer, 60 for nurture, and our deliverability team finally has a knob they can tune.
David H.GTM Lead, Snowflake
Trust & compliance
Enterprise-grade security and scale
Every layer of the stack carries a third-party attestation, so you can ship into regulated industries without rebuilding your compliance posture.
SOC 2 Type II
Independently audited to the SOC 2 Type II standard.
GDPR
Built for the EU with full GDPR data-subject rights.
CCPA
California opt-out, do-not-sell, plus DSAR handling.
ISO 27001
Information security held to the ISO 27001 standard.
ISO 42001
AI governance aligned to the new ISO 42001 standard.
Common questions
Mail domain lookups, answered
The questions we get from teams that land here to look up a domain's mail setup, what the result shows, why a domain might not accept mail, and where the lookup fits in the deliverability picture.
What is a mail domain lookup?
A mail domain lookup takes a single domainand reads back its whole mail configuration: the provider that runs the domain's email, the MX records that route mail to it, and whether the domain is set up to receive mail at all. Type a domain into the tool above and Verifox returns that snapshot.
Where a raw record lookup makes you read hostnames, a mail domain lookup answers the orienting question first, who handles this domain's mail and is it configured. It is the same DNS resolution our verification engine performs before it ever touches a mailbox.
How do I find the mail server for a domain?
Paste the domain into the lookup above and read the result. The mail server, or servers, for a domain live in its MX records, and Verifox lists them in priority order along with the provider behind them. No account, no install.
You can also query it from a terminal with nslookup -type=mx example.com or dig example.com MX, but those return raw hostnames you then have to decode. If you want every record read literally, the MX records in detail page does exactly that.
How do I find out which provider hosts a domain's email?
The mail provider is written into a domain's MX hostnames, and a mail domain lookup reads it for you. Hosts ending in aspmx.l.google.com mean Google Workspace, mail.protection.outlook.com means Microsoft 365, and a custom hostname usually points to a self-hosted or niche provider.
Verifox names that provider in plain English rather than leaving you to recognise the hostnames, which is the fastest way to learn who hosts a domain's email before you reach out to it or add it to a sending list.
What does a mail domain lookup tell me?
Three things at a domain level. First, who runs the mail, the provider behind the MX records. Second, how mail routes, the MX records in priority order, with the primary server and its fallbacks. Third, whether mail is accepted, a domain with no MX record cannot receive email at all.
It is the overview that sits above the two detail views, the MX records in detail and the SPF, DKIM, and DMARC detail. To then confirm a specific address is reachable, the mailbox itself has to be checked, which a domain lookup alone cannot do.
Why does a domain not accept email?
Usually one of two reasons shows up in a mail domain lookup: the domain publishes no MX records, so there is nowhere for mail to land, or the domain itself does not resolve, a typo, an expired registration, or a DNS misconfiguration. Either way, mail sent to it will bounce.
Some domains intentionally have no MX and route mail another way, but for most a missing MX is a real problem. If you are chasing bounces, the domain lookup is the first place to look, then the authentication detail covers whether SPF, DKIM, and DMARC are landing your mail in the inbox.
Is a mail domain lookup the same as looking up MX records?
They overlap, but a mail domain lookup is the broader of the two. An MX lookup reads the MX records literally, the hosts and their priorities. A mail domain lookup wraps that in the domain-level picture, naming the provider and giving a yes-or-no on whether the domain can receive mail.
Think of it as the overview versus the detail. Start here for who runs the mail and is it set up, then drop into the MX page when you need to read each record, or the SPF, DKIM, and DMARC page when you need the authentication strings themselves.
Can I look up the mail setup for many domains in bulk?
Yes. The single lookup above is free with no account. For a list of domains, the REST API returns the MX records and the detected provider for each one, so you can run a bulk mail domain lookup across a whole list programmatically.
Bulk lookups run on the same pay-as-you-go credits as the rest of the platform, localized to your region, and those credits never expire. One credit covers a single domain lookup.
Does a mail domain lookup confirm an email address works?
No, and the difference matters. A mail domain lookup checks the domain, can it receive mail at all and who runs it. Confirming an email checks the specific mailbox, does jane@example.com actually exist and accept mail.
A domain can have a flawless mail setup while a given address on it is dead. That is why a domain lookup is step one of deliverability and the free email checker is step two. Verifox runs both on the same engine.
Does Verifox store the domains I look up?
No. The domain you enter is resolved in memory and discarded the moment the lookup completes. Nothing logged, nothing retained, nothing sold. A domain's mail configuration is public DNS data, but your queries are still yours.
Verifox is SOC 2 Type II compliant and GDPR ready. The full breakdown of what we touch and what we do not is in the privacy policy.
Can I run a mail domain lookup from my own app or AI agent?
Yes. The REST API reference documents a lookup endpoint that returns the MX records and the detected provider for any domain, so you can wire domain mail lookups into your CRM, your onboarding flow, or any tool that speaks REST.
Verifox also ships native MCP server support, so AI agents (Claude, Cursor, custom LLM apps) can look up a domain's mail setup and verify addresses without glue code. Live uptime and incident history are at status.verifox.ai.