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DNS Record Checker

Q: What does this DNS checker check?

It looks up your MX, SPF, DKIM (on the 20 most common selectors) and DMARC records, validates each one and gives you the exact fix for anything broken.

Q: Why wasn't my DKIM found?

DKIM sits under a selector that only you or your provider know, so there's no way to list every key a domain has. We try the most common selectors. If yours is custom, read the s= value from the DKIM-Signature header of an email you sent and check it in the DKIM Checker.

Q: How long do DNS changes take to show?

Usually a few minutes. If the old record had a long TTL, it can take up to 48 hours for every resolver to drop it. Run the check again after you update a record.

Q: Is this a DNS propagation checker?

Partly. It queries public resolvers from Cloudflare and Google, so it shows what most of the internet sees right now. It doesn't compare results from dozens of locations the way a dedicated propagation tool does.

Q: My records pass. Why do I still land in spam?

Passing records prove who you are. Where you land depends on reputation, engagement and content. Run a free Email Deliverability Test to see placement per provider, then work on the signal that's weakest.

Q: What DNS records do I need to send email?

At minimum SPF and DKIM for every service that sends as your domain, plus DMARC if you send in volume to Gmail, Yahoo or Outlook users. You'll also want MX so replies and bounces can reach you. If you run your own mail server, ask your hosting provider for a PTR record that matches your sending host name.

Q: Do I need a PTR record if I use Google Workspace or Microsoft 365?

No. The PTR record belongs to whoever owns the sending IP, and Google and Microsoft manage it for theirs. You only need to arrange one for IPs you control, such as a dedicated server or a dedicated IP from your hosting provider.

One lookup, full picture: check your SPF, DKIM, DMARC and MX records, see what's broken, and get the exact fix for each.

✓SPF, DKIM, DMARC, MX
✓Exact fixes
✓No sign-up needed

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How it works

Your email DNS, checked in one go

01
Enter your domain
One lookup checks all four email records at once.
02
MX & SPF
Mail servers, SPF syntax and the 10-lookup limit.
03
DKIM & DMARC
Key strength, policy, alignment and reports.
04
Fix and re-check
Apply each fix, then run it again to confirm.

Email DNS records explained: what each one does

Four DNS records decide whether your email is delivered and trusted, and a fifth helps your IP look legitimate. The email DNS checker above reviews MX, SPF, DKIM and DMARC in one lookup. This table shows what each record does and where it usually breaks.

Record	What it does	Where it lives	Typical error
MX	Receives mail for your domain	yourdomain.com	Missing, or still pointing to an old provider
SPF	Lists servers allowed to send for you	TXT on yourdomain.com	Over 10 DNS lookups, two records
DKIM	Signs each message	TXT at selector._domainkey	Signing never switched on
DMARC	Tells receivers what to do when checks fail	TXT at _dmarc	Stuck at p=none, no reports
PTR (rDNS)	Maps your sending IP back to a hostname	Set by your IP owner	Missing on self-hosted servers

What DNS records you need to send email

Every domain that sends mail needs SPF and DKIM, and Gmail and Yahoo require a DMARC record from anyone sending 5,000 or more messages a day to their users. MX is needed to receive replies and bounces. If you send through Google Workspace, Microsoft 365 or a major email platform, the provider manages the PTR record for its IPs. If you run your own server, you have to ask your hosting provider to set it. More on that in why PTR records matter for deliverability.

The order to set up email authentication

Start with MX so the domain can receive mail. Add one SPF record that covers every service sending as you. Turn on DKIM signing in each of those services and publish their keys. Publish DMARC with p=none and a rua address so reports start coming in. Once the reports show every legitimate sender passing, move the policy to quarantine and then reject. The SPF, DKIM and DMARC checkers go deeper into each step.

If the checker can't find DKIM while your provider says it's on, the key is probably published under a custom selector. Look up the s= value in the headers of a sent message and check it in the DKIM Checker directly.

DNS changes and propagation

Changes don't show everywhere at once. Each record has a TTL, the time other servers may keep the old value cached, often between five minutes and a day. If a new record doesn't appear here, wait for the old TTL to pass and check again. Our article on DNS propagation explains how to plan changes around it.

Next step when all records pass

Passing records prove to receivers who you are. Where your mail lands from here depends on reputation, engagement and content, so run a free Email Deliverability Test to see the result at Gmail, Outlook and Yahoo. Warmy then builds that reputation with warm-up from real mailboxes and re-checks your DNS every day.

Records all green? Let Warmy build your inbox reputation. Try it free for 7 days or book a demo.

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Why Warmy

Everything Deliverability
In One Platform

One platform, one subscription, one team, no add-ons, no extra vendors.

Scale & people

1M+ real mailboxes - The largest warm-up network — genuine Workspace, Microsoft 365 and consumer inboxes.
A dedicated success manager - A named expert who owns your placement outcomes, not a ticket queue.
24/7 support, VIP channels - Real people any hour, in your own Slack, WhatsApp or Teams channel.
120+ deliverability specialists - The largest team in the category, dedicated to inbox placement.
An in-house research team - Continuous experiments on how Gmail, Outlook and Yahoo filter this month.
Recognised experts - Specialists who advise on sender reputation daily — not generalists.

Technology

Adeline AI co-pilot - Reads your tests, DNS and warm-up data, then tells you what to fix next.
The infrastructure behind other tools - Outreach platforms and ESPs run their warm-up on our API.
One loop: test, warm, fix - Placement tests, warm-up, monitoring and fixes in a single platform.
500K+ US seed accounts - Real inboxes across major, corporate and regional providers — mobile included.
Monthly seed rotation - Aging mailboxes retire automatically, so your data comes from live inboxes.
Automation built in - n8n, Zapier, Make and a documented API — no CSVs, no manual seed files.

Included in every plan

Email verification - Clean lists before you send, so bounces never cost you reputation.
DMARC tracker - SPF, DKIM and DMARC monitoring with the exact record to change.
Deliverability tester - Instant placement, authentication and blacklist check for any sender.
Templates AI optimizer - Your campaign scored and rewritten for the inbox before you send.
Reputation tracker - Domain and IP reputation with blacklist alerts the moment a signal drops.
Google Postmaster built in - Postmaster data beside your warm-up and placement results.
Working-hours warm-up - Natural business-hours sending in the recipient’s time zone.
A robust API - Every feature available over documented endpoints.

No extra vendors, no add-on fees, no separate contracts.

Loved By Thousands Of Marketers Around The World

Over 7,000 Businesses Trust Warmy

FAQ

DNS Checker
Questions, Answered

Which DNS records matter for email?

Four of them do the main work. MX receives your mail, SPF lists who may send for you, DKIM signs your messages, and DMARC tells receivers what to do when SPF or DKIM fail. Gmail and Yahoo require all of them from bulk senders.

What does this DNS checker check?

Why wasn't my DKIM found?

How long do DNS changes take to show?

Is this a DNS propagation checker?

My records pass. Why do I still land in spam?

What DNS records do I need to send email?

Do I need a PTR record if I use Google Workspace or Microsoft 365?

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DNS Record Checker

Your email DNS, checked in one go

Enter your domain

MX & SPF

DKIM & DMARC

Fix and re-check