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Planning & calculators
Mailbox & Volume Planner
Enter a monthly send target and get the number of domains and mailboxes required at a safe per-mailbox daily limit.
All free toolsFree · nothing stored
Your send target
30 sends per mailbox per day is the ceiling we recommend on Google Workspace. Higher works until it very suddenly does not.
What you need
Mailboxes
46
Domains
16
Sends per day
1,364
Monthly cost
$184
Cost per 1,000 sends$6.13
Sends per mailbox per month660
Ramp time to full volume3 to 4 weeks from cold
Rules of thumb
- • Never send from your primary domain. Use lookalike domains that redirect to it.
- • Two to three mailboxes per domain. More concentrates the blast radius.
- • Warm every mailbox for at least two weeks before it touches a real list.
- • Keep bounce rate under 2% and reply rate above 1% or slow down.
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