Free Email Warmup Calculator
Enter your target sending volume and get a day-by-day warmup schedule. Know exactly how many emails to send each day.
How it works
Enter your target daily volume
How many emails per day do you want to reach after warmup?
Choose a growth model
Linear (steady increase) or exponential (slow start, fast ramp).
Get your day-by-day schedule
A 30-day plan showing exact daily send volumes with safety thresholds.
Why this matters
New mailboxes and IPs have no sender reputation. Sending too many emails too fast triggers spam filters and can permanently damage your deliverability. A gradual warmup builds reputation safely. Most deliverability problems come from skipping or rushing this step.
Warmup on autopilot
SendKit warms up every new mailbox automatically with human-like sending patterns. No schedules to manage.
Automated warmup
SendKit warms up your mailboxes automatically with human-like sending patterns
Reputation monitoring
Real-time tracking of your sender reputation across all mailboxes
Auto-pause protection
Automatically pauses sending if reputation drops below safe levels
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Got questions? We've got answers.
Most mailboxes need 2-4 weeks of gradual warmup before reaching full sending volume. The exact timeline depends on your target volume and the age of your domain.
Ready to hit primary?
Set up SendKit's isolated infrastructure and start sending in under 15 minutes.
Dedicated IPs on every plan. Cancel anytime.