Free SPF, DKIM, DMARC and MX checker

Is your domain ready to send?

Check SPF, DKIM, DMARC and MX for any domain in seconds, with plain-English fixes for anything that's missing.

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What we check

Four records every sender needs.

MX

Where mail for your domain is delivered. Without it, replies and bounces have nowhere to go, and some inboxes treat you as suspicious.

SPF

A list of the servers allowed to send as your domain. There should be exactly one SPF record, ending in ~all or -all.

DKIM

A signature that proves an email wasn't altered on the way. Each sending service publishes its own key under a selector.

DMARC

Tells inboxes what to do when SPF or DKIM fail. Gmail and Yahoo require it for bulk senders. Start with p=none, then tighten.

How SendNova protects your domain once these are set up

Fix it

How to fix the most common problems.

Every fix is a DNS record you add or edit where your domain is managed: your registrar or DNS host. Copy the example, swap in your own values, and run the check again.

SPF: one record that lists every sender

SPF is a TXT record on your root domain listing the services allowed to send as you. A typical record for a domain that sends through Google Workspace:

v=spf1 include:_spf.google.com ~all

Common mistakes

Two SPF records. Receivers treat that as an error. Merge them into one record with several include: parts.
More than 10 DNS lookups. Each include: counts. Remove services you no longer use.
Ending in +all. That lets anyone send as you. End with ~all or -all.
A missing service. Add an include: for every tool that sends email from your domain.

DKIM: turn on signing with your provider

DKIM is a public key your email provider generates. You publish it as a TXT record at selector._domainkey.yourdomain.com, then switch signing on in the provider's settings:

google._domainkey  TXT  "v=DKIM1; k=rsa; p=MIIBIjANBgkq..."

Common mistakes

Wrong selector. The selector is the first part of the name, for example google or s1. Copy it exactly from your provider.
Record published, signing off. Most providers need you to press "start authentication" after the record goes live.
A broken key. Long keys are sometimes split or cut off when pasted. Paste the full value as one string.
A 1024-bit key. It still works, but 2048-bit is the current recommendation.

DMARC: start with monitoring, then tighten

DMARC tells inboxes what to do when SPF or DKIM fail, and where to send reports. Add a TXT record at _dmarc.yourdomain.com:

v=DMARC1; p=none; rua=mailto:dmarc@yourdomain.com

Common mistakes

Jumping straight to p=reject. Watch the reports for a few weeks first, then move to p=quarantine and later p=reject.
Two DMARC records. Keep exactly one at _dmarc.
No alignment. The domain in your From address must match the domain that passes SPF or DKIM.
No report address. Without rua you can't see who is sending as you.

MX: make sure replies have somewhere to go

MX records tell the world which servers receive mail for your domain. A domain on Google Workspace has a single MX record:

yourdomain.com  MX  1  smtp.google.com

Common mistakes

No MX record at all. Replies and bounces fail, and some inboxes treat the sender as suspicious.
Records left from an old provider. Remove MX records for services you've moved away from.
An MX pointing at an IP address. MX values must be host names, not IPs.

Inbox rules

What Gmail and Yahoo ask of senders.

Since February 2024, Gmail and Yahoo require authentication from everyone, and stricter rules for anyone sending around 5,000 or more emails a day to their users.

Everyone

SPF or DKIM set up for the sending domain
Valid forward and reverse DNS for sending servers
Spam complaint rate kept below 0.3%
Messages sent over a secure (TLS) connection

Bulk senders also need

Both SPF and DKIM
A DMARC record, at least p=none
A From domain aligned with SPF or DKIM
One-click unsubscribe, honoured within two days

See how SendNova paces sending to stay inside these limits

Questions

Email setup, plainly answered.

Still stuck on a record? Email support@sendnova.io and a person will look at it with you.

What is an SPF record?

A TXT record on your domain that lists the services allowed to send email as you. Receiving inboxes check it to spot forged senders.

Can I have two SPF records?

No. Two SPF records on one domain cause an SPF error. Combine them into a single record, for example v=spf1 include:_spf.google.com include:sendgrid.net ~all.

What DMARC policy should I start with?

Start with p=none and a report address, so nothing is blocked while you check that every real sender passes. Then move to p=quarantine, and finally p=reject.

How do I find my DKIM selector?

Your email provider shows it where you set up DKIM. You can also open any email you've sent, view the original message, and read the s= value in the DKIM-Signature header.

Do I need DMARC if I only send a little email?

Gmail and Yahoo only require it for bulk senders, but it's a single record, it protects your domain from spoofing, and it helps every inbox trust you. It's worth adding.

How long do DNS changes take?

Usually a few minutes to a few hours. Some providers take up to 48 hours. Run the check again once your DNS host shows the new record.

Is the checker really free?

Yes. There's no sign-up, and we don't store the domains you check. Lookups run in your browser against public DNS.

Your next email is two lines away.

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