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Mailbox calculator
How many inboxes do you actually need?
Enter your monthly volume and we will size the domains, inboxes and warm-up plan the way we do for client programmes.
We keep warmed inboxes between 15 and 30.
Spare warmed inboxes to swap in when a domain needs a rest.
0emails per sending day
0inboxes you need, including reserve
0sending domains
$0estimated infrastructure per month
launch plan
Buy domains + inboxestoday
Warm-up runsabout 14 days
Earliest cold send—
Full volume—
Rule of thumb, not a guarantee. Volume per inbox should ramp gradually after warm-up, and Google and Microsoft inboxes behave differently. Prices are editable because they vary by provider. Read the reasoning in our inbox math post.
Next step
Rather have us run it?
These tools are the checks we run on every programme. If you want the whole engine built and run for you, book a strategy call.