Email Deliverability API

SPF (Sender Policy Framework), DKIM (DomainKeys Identified Mail), and DMARC (Domain-based Message Authentication, Reporting & Conformance) are three complementary email authentication protocols that work together to protect your domain. SPF verifies that emails claiming to be from your domain actually come from authorized mail servers by checking the sender's IP address against a published list. DKIM uses cryptographic signatures to verify that email content hasn't been altered in transit and that the message was authorized by the domain owner. DMARC builds on both SPF and DKIM by specifying what receiving servers should do when authentication fails and provides reporting mechanisms to monitor your email ecosystem. Together, these three protocols create a robust defense against email spoofing, phishing attacks, and domain impersonation.

The deliverability score is calculated based on the presence and proper configuration of essential DNS records (SPF, DKIM, DMARC), the validity of PTR records, and the overall health of the domain's email infrastructure. The score ranges from 0-100, with higher scores indicating better deliverability prospects. Each component contributes to the overall score, with properly configured security records significantly boosting the rating.

A PTR (Pointer) record, also known as reverse DNS, maps an IP address back to a domain name. Many email servers check PTR records to verify that incoming messages are coming from legitimate servers. Without a valid PTR record, your emails may be flagged as spam or rejected entirely by receiving servers. The PTR record should match the domain used in your email's HELO/EHLO commands for best deliverability results.

The API provides specific improvement suggestions based on your domain's current configuration. To implement these improvements, you'll typically need to add or modify DNS records through your domain registrar or DNS hosting provider. For SPF, DKIM, and DMARC records, you'll need to add TXT records with specific formats. For PTR records, you may need to contact your email hosting provider or ISP, as these records are typically managed at the IP level rather than the domain level.

It's recommended to check your domain's deliverability at least monthly, especially for businesses that rely heavily on email communication. Additionally, you should check after making any changes to your email infrastructure, DNS records, or when switching email service providers. Regular monitoring helps ensure that your email configuration remains optimal and allows you to quickly address any issues that might affect deliverability. For high-volume senders or businesses where email is mission-critical, weekly checks or even automated daily monitoring may be appropriate. Set up alerts to notify you when your deliverability score drops below acceptable thresholds.

Yes, the Email Deliverability API excels at identifying email spoofing vulnerabilities through comprehensive DMARC analysis. The API checks if your DMARC policy is set to 'none', 'quarantine', or 'reject' — domains with no DMARC policy or a policy set to 'none' are vulnerable to spoofing attacks where malicious actors can send emails that appear to come from your domain. The API also validates that your SPF records aren't overly permissive (using '+all' is a major security risk) and checks for the presence of DKIM selectors. By examining all three authentication mechanisms together, the API can identify specific attack vectors and provide actionable recommendations to harden your email security posture. Regular scans help ensure unauthorized parties cannot impersonate your domain to commit phishing or fraud.