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Free Email Tools
Check your domain’s SPF, DKIM and DMARC, trace where an email went wrong, and write better subject lines and signatures.
- No signup
- Runs in your browser
- Nothing stored
Get your email into the inbox
- northwind.co1 to fixMXPassSPFPassDKIMPassDMARCWeak
Email Domain Checker
Check MX, SPF, DKIM and DMARC at once and see what to fix.
- northwind.coEnforcedp=rejectnonequarantinereject
DMARC Checker
See a domain’s DMARC policy, every tag in plain language and the next step to enforce it.
- TXT · _dmarcCopyv=DMARC1;
p=quarantine;
rua=mailto:dmarc@northwind.coDMARC Generator
Pick a policy and report addresses, then copy a valid record for your DNS host.
- 3 hops · 1.6 sDeliveredSender0.4 sRelay1.2 sInboxSPFDKIMDMARC
Email Header Analyzer
Paste an email’s headers to see its route, delays and authentication results.
Make every email look right
- Subject lineStrong86
Your March invoice is ready
- Fits on mobile
- No spam triggers
Email Subject Line Tester
Score a subject line, preview it in an inbox and compare versions.
- Signature previewHTMLAMAlex MorganHead of Growth · Northwindalex@northwind.co
Email Signature Generator
Build an HTML signature with your logo and colors for Gmail, Outlook and Apple Mail.
Emails going to spam? Three checks fix most problems
- 1
Check your domain
See whether MX, SPF, DKIM and DMARC are in place and valid.
Email Domain Checker - 2
Fix DMARC
Create a valid record, then move from p=none to quarantine and reject.
DMARC Generator - 3
Check a real message
Paste the headers of an email that went to spam to see what failed.
Email Header Analyzer
Free email tools FAQ
Are these email tools really free?
Yes. Every tool here is free to use as often as you like. There’s no account, no email signup and no ads.
Do you see or store what I enter?
No. The tools run in your browser. The Email Header Analyzer, Subject Line Tester and Signature Generator never send what you type anywhere. The domain checks send only the domain name to public DNS resolvers (Google, or Cloudflare as a backup), and nothing is stored.
My emails go to spam. Which tool should I start with?
Start with the Email Domain Checker to make sure SPF, DKIM and DMARC are set up. Then paste the headers of an email that landed in spam into the Email Header Analyzer to see which check failed.
What’s the difference between the Domain Checker and the DMARC Checker?
The Email Domain Checker gives an overview of all four email records: MX, SPF, DKIM and DMARC. The DMARC Checker goes deeper into DMARC alone: the policy, every tag, where reports go and the next step to enforce it.
Do I need an Atomic Mail account to use them?
No. The tools work for any domain and any email provider. If you’d like encrypted email on your own domain, Atomic Mail Business shows you the records to add when you connect it.
Email on your own domain, set up the right way
When you connect your domain, Atomic Mail shows you the MX, SPF, DKIM and DMARC records to add. Mail between your team is end-to-end encrypted, with no ads and no tracking.
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