Check your email deliverability in 30 seconds.
Type your sending domain and the Signal Engine reads 2 of the 7 Inbox Signals instantly from public DNS and blacklist data. Want the other 5? Sign up free and upload a CSV or connect your ESP.
Step 1 · Enter your sending domain
30 seconds · No signup · No credit card · Reads Authentication Standing + Domain Reputation
The 7 Inbox Signals, explained
Every signal the engine reads, the weight we give it, and what it measures.
01 · Bounce Exposure
25 pts of 100
Historical bounce rate + predictive risk from role, disposable, and catch-all flags.
02 · Engagement Trajectory
25 pts of 100
Real human engagement over 30 days, MPP-adjusted per ESP.
03 · Acquisition Quality
15 pts of 100
Day-1 engagement per acquisition cohort. Which channel is dragging your list down.
04 · Domain Reputation
15 pts of 100
Sender-domain blocklist status + recipient provider concentration.
05 · Spam Trap Exposure
10 pts of 100
Probabilistic trap risk from dormancy depth, list age, acquisition pattern.
06 · Authentication Standing
5 pts of 100
SPF + DKIM + DMARC + List-Unsubscribe vs 2024-2025 ISP mandates.
07 · Decay Velocity
5 pts of 100
Rate of change in your composite Signal Score. Trend language, no fake day counts.