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Enter how many new contacts you add a week and how many steps your sequence has. See the daily sends once every step is running, how the first weeks ramp up, and the inboxes and domains it takes to send them.
Enter the new contacts you add each week, the steps in the sequence and the working days you send on. Then set the cold emails per inbox a day and the inboxes per domain, as a range. Warm-up weeks are optional. The calculator shows the sends per working day once every step is running, the sends in each week of the ramp, the inboxes and domains you need, and the week the sequence is full.
Short answer: Multiply the new contacts you add each week by the steps in your sequence, then divide by working days. That is your daily send once every step is running. Divide by each inbox's daily limit for inboxes, then by inboxes per domain for domains. 250 contacts a week on four steps is 200 sends a day.
Follow-ups spend the same daily limit as first emails. That is why the step count sits in the formula, and why the length of your sequence decides how many new people each inbox reaches.
This is the example from how many cold emails per day per inbox: 250 new contacts a week, four steps, five working days.
| Sending week | Steps live | Sends that week | Per working day |
|---|---|---|---|
| 1 | 1 | 250 | 50 |
| 2 | 2 | 500 | 100 |
| 3 | 3 | 750 | 150 |
| 4 onward | 4 | 1,000 | 200 |
At 25 cold emails per inbox a day, 200 sends need 8 inboxes. At 15 they need 14. With two or three inboxes per domain, that is 3 to 4 domains at 25, and 5 to 7 at 15. Week one alone needs 2 inboxes. Week four needs 8, so set them all up before launch.
The 179 inboxes we sent cold email from on 16 October 2026 were set to 15 to 33 a day, median 30. They sat on 70 domains, two or three inboxes each. The calculator starts at 25. I would not copy 33: 14 of our 62 inboxes at that setting showed sender bounce rates of 10.6% to 19.7% over three days.
Google, Yahoo and Microsoft publish no per-inbox limit for cold email. Google Workspace caps an account at 2,000 messages a day and 3,000 external recipients, over a rolling 24 hours (Google Workspace sending limits, checked 21 October 2026). That is an account ceiling, not a cold email setting.
Multiply new contacts a week by the steps, then divide by working days. 250 a week on four steps over five days is 200 a day once the sequence is full.
In week one only first emails go out. Each week after adds the next step for earlier contacts, so on four steps the volume climbs 250, 500, 750, then holds at 1,000.
No. Warm-up moves the first send later. It does not change the volume. We allow two to three weeks on new domains, so after three weeks of warm-up a four-step sequence is full in week 7.
The same number of sends as your new contacts, every week. At 250 a week that is 250 more sends a week, 50 more a day, and 10 inboxes at 25 instead of 8. Our step-by-step reply data says when a fifth step is worth it.