6 deliverability tools — all free

Know exactly why your
emails land in spam.

Blocklist monitor, domain reputation, header analyzer, content scorer, seed testing, and warmup planner — everything to diagnose and fix deliverability.

Blocklist Monitor
Check if your domain or IP is listed on 12+ major spam blacklists instantly.
Domain Reputation
Full DNS health check — SPF, DKIM, DMARC, MX records, domain age, and sender score.
Email Header Analyzer
Paste raw email headers to detect spam signals, routing issues, and authentication failures.
Content Score
Paste your email subject and body to get a spam score and actionable fixes.
Seed Inbox Testing
Enter the subject line of an email you just sent to simulate inbox placement across 8 major providers.
Warmup Planner
Calculate the optimal warmup schedule for your domain based on your target volume and starting point.