Starting May 5, Microsoft will require DMARC.

Check if your domain is compliant.
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SPF Checker

Check your domain's SPF record configuration. Verify which IP addresses are authorized to send email on behalf of your domain and optimize your record to prevent authentication failures.

What is SPF?

SPF (Sender Policy Framework) is an email authentication method that allows domain owners to specify which IP addresses and mail servers are authorized to send email on behalf of their domain. It helps prevent email spoofing and improves deliverability.

Sender Authorization

Define which IP addresses and servers are authorized to send email on behalf of your domain.

Prevent Email Spoofing

Stop unauthorized senders from impersonating your domain in phishing attacks.

Improve Deliverability

Increase the likelihood that your legitimate emails reach the inbox instead of spam folders.

Reduce DNS Lookups

Optimize SPF records to avoid the 10 DNS lookup limit that can cause authentication failures.

SPF Record Mechanisms

SPF records end with an "all" mechanism that defines what happens to emails that don't match any of the authorized senders:

Transitional protection

~all

Soft fail - mark messages that fail SPF check as suspicious

Maximum protection

-all

Hard fail - reject messages that fail SPF check

Not recommended

?all

Neutral - take no action based on SPF check

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How Skysnag Simplifies SPF

Skysnag automates SPF record management, ensuring your records are optimized, up-to-date, and never exceed the DNS lookup limit that can cause authentication failures.

Automatic Flattening

Convert nested SPF records to avoid the 10 DNS lookup limit

Source Discovery

Automatically detect all legitimate email sources for your domain

Real-time Updates

Keep your SPF record current as your email infrastructure changes

Validation Testing

Continuously test your SPF record to ensure it's working correctly

DMARC Alignment

Ensure your SPF record aligns properly with your DMARC policy

Performance Monitoring

Monitor SPF authentication rates and identify delivery issues

SPF Implementation Results

See the impact of optimized SPF implementation with Skysnag

99.8%

SPF authentication rate

85%

reduction in DNS lookup failures

100%

automated record maintenance

24/7

monitoring and optimization

Talk to an expert to review your authentication gaps.

Meet with one of our experts to review your report. We'll walk you through the issues, explain the security gaps, and show you exactly how Skysnag resolves them - automatically.

Discuss my results

See everything Skysnag has to offer

Skysnag gives you everything you need to enforce DMARC, automate SPF and DKIM, deploy MTA-STS and TLS-RPT, and activate BIMI - so your emails are secure, compliant, and trusted.

Monitor

Identify email compromise attempts and troubleshoot email delivery issues

Comply

Comply with Microsoft, Google and Yahoo requirements and visualize sending data in real-time

Protect

Automate DMARC enforcement for unparalleled email security

Certify

Certify your brand with the highest identity standard globally

Start for free