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Cold email sequence capacity calculator
Estimate aggregate message capacity after reservations and the minimum capacity-days for a complete sequence.
Prepare your inputs
Count only selected, eligible mailboxes. Reserve daily slots for warmup, other campaigns and ordinary business mail before estimating first-step capacity. Enter limits you have already reviewed, not aspirational targets.
Runs in this browser. Inputs are not sent by this tool or saved in browser storage. Start with the fictional example; use redacted text for reviews.
How it works
Available daily slots equal mailboxes multiplied by daily cap minus reservations. Worst-case demand equals leads multiplied by sequence steps. Dividing demand by available slots gives a capacity bound, not a schedule.
Worked example
Three mailboxes at 20 slots each with 15 reserved leave 45 daily slots. A 100-lead, three-step sequence has 300 possible messages and needs at least seven capacity-days before timing constraints.
Limits and interpretation
The estimate assumes every lead receives every step. Replies, stop rules, windows, provider quotas and sequence delays change actual demand and elapsed time.
Examples are synthetic, not customer results. Zintara practical guide library