The Blog
Hard-won lessons on email verification, inbox placement, and keeping your sender reputation spotless — from the team that's been verifying email since 2000.
Anti-spam laws and compliance: CAN-SPAM, GDPR, CASL
Understand how DKIM signature reuse impacts spam filter alignment. Learn the real technical implications and how MailTester’s deliverability tests help.
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Resolve sts-policy-fetch-error by validating domain configurations and email addresses. Reduce bounces and improve inbox placement with real-time.
Understand how DNS caching delays disrupt SPF verification and reduce email deliverability. Fix it with real-time validation and proactive list hygiene.
Verify internationalized email domains accurately with MailTester’s real-time API. Reduce bounces, improve deliverability, and keep your list clean with.
Compare Rspamd spam scoring and SpamAssassin Bayesian filtering accuracy. Learn how validation prevents deliverability issues and improves inbox placement.
Monitor inbox placement for your Shopify emails with real-time domain testing to reduce bounces and boost deliverability.
Detect punycode spoofing in real time with MailTester’s email verification API. Prevent phishing and protect your domain reputation with accurate, instant.
Learn how SPF alignment and BCC usage impact email verification accuracy. Prevent false positives and improve inbox placement with real-world insights.
Test and verify email addresses instantly from the command line with real-time response codes.
Stop ghost newsletter sending delays caused by upstream rate limits and flawed email validation.
Use sender behavior and domain history to implement advanced SpamAssassin meta rules that boost deliverability, reduce spam, and prevent inbox failure.
Fix SPF limitations that block valid emails. Reduce bounces, improve deliverability, and verify sender compliance with real-time email checks.
Stay sharp
Occasional, practical notes on verification and inbox placement. No spam — we'd be embarrassed.
