Knowledge base
Everything you need to know about email authentication, deliverability, and making sure your emails reach the inbox.
Authentication
SPF records explained: how they protect your domain
Learn how Sender Policy Framework (SPF) records work, why they matter, and how to set one up correctly.
DKIM: how email signing works
Understand how DomainKeys Identified Mail (DKIM) cryptographically signs your emails to prove authenticity.
DMARC: protecting your domain from spoofing
How DMARC ties SPF and DKIM together to prevent email spoofing and phishing attacks using your domain.
BIMI: display your brand logo in email inboxes
Learn how BIMI helps you display your logo next to emails, increasing brand visibility and trust.
MTA-STS: enforcing TLS encryption for email
How MTA-STS prevents downgrade attacks and ensures emails are always transmitted over encrypted connections.
ARC: preserving authentication through forwarding
Understanding Authenticated Received Chain and why it matters for mailing lists and forwarding.
Deliverability
Why emails go to spam (and how to fix it)
The common reasons emails land in spam folders and actionable steps to improve your inbox placement.
Email warm-up: building sender reputation
How to properly warm up a new domain or IP address to build trust with email providers.
Understanding blacklists and how to get delisted
What email blacklists are, how to check if you're listed, and steps to request removal.
The 10 SPF lookup limit: why it matters
Understanding the SPF DNS lookup limit and strategies to stay under it with multiple email services.
DMARC policy progression: from none to reject
A step-by-step guide to safely moving from monitoring mode to full DMARC enforcement.
Infrastructure
MX records: how email routing works
Understanding Mail Exchange records and how they direct email to the right servers.
Reverse DNS (PTR records) for email servers
Why PTR records matter for email deliverability and how to set them up correctly.
TLS-RPT: monitoring email encryption failures
How to set up TLS Reporting to receive alerts when email encryption fails.
Choosing an email service provider
Key factors to consider when selecting an ESP for transactional or marketing email.
Best Practices
Setting up email authentication for new domains
A complete checklist for configuring SPF, DKIM, and DMARC on a brand new domain.
Email authentication with multiple sending services
How to properly configure authentication when using multiple ESPs and email tools.
Monitoring and understanding DMARC reports
How to read DMARC aggregate reports and use them to improve your email authentication.
Subdomain strategy for email sending
When and how to use subdomains for different types of email to protect your main domain reputation.
Check your domain health
See how your domain scores on email authentication and deliverability.
Scan your domain