Cold Email Infrastructure Planner
How many domains and inboxes does your sending volume actually need? Warmup timeline and monthly cost included.
Free · no signup · last reviewed August 29, 2026
5
Inboxes needed
2
Domains needed
$17
Est. monthly cost
The timeline nobody tells you: new inboxes need at least 14 days of warmup before real sending, and 21–30 days is safer. Buy domains and start warmup a month before you need the volume — infrastructure is the part of cold email you can’t rush.
Our defaults are deliberately conservative: 30 sends/inbox/day and 3 inboxes/domain protect deliverability at the cost of needing more inboxes. Cost assumes ~$3/inbox/month and ~$11/domain/year at commodity providers — estimates, and they drift.
Methodology & honest limits
How it works: inboxes = target daily sends ÷ sends-per-inbox; domains = inboxes ÷ inboxes-per-domain; cost assumes ~$3/inbox/month and ~$11/domain/year at commodity providers. Our defaults (30/inbox, 3/domain) are deliberately conservative — they protect deliverability at the price of more inboxes.
Honest limits: these are our planning defaults, not laws — some senders push 50+ per inbox and get away with it until they don’t. The unskippable constant is warmup: 14 days minimum before real volume, 21–30 safer. Provider prices drift; treat the cost as an estimate.
Keep going
This is the work. Want it done?
Everything here is free to use yourself — that’s the point. If you’d rather a senior marketer just handle it, in your accounts and your name: 20-minute call, no pitch deck.