How many leads a day
can your inboxes take?
Not your send volume. Every lead consumes one send per sequence step, so the rate you can actually sustain is a much smaller number, and it is the one that decides whether a campaign works in its second week.
Runs in your browser, nothing is sent anywhere
Your fleet
What that supports
48
new leads a day, against 240 sends a day. The two are not the same number, and planning against the second is the usual mistake.
| Sends the fleet can place a day | 240 |
|---|---|
| Sustainable new leads a day | 48 |
| Days until the full load arrives | 12 |
| Working days of runway | add a list size |
Your configured limit is the binding one: the mailboxes can physically place 36 sends each inside the window, which is more than the 30 they are set to. Widening the window would change nothing.
Cheapest lever
Shorten the sequence. Going from 5 steps to 4 raises the sustainable rate by about 25 per cent, immediately and for nothing.
The defaults are illustrative, not measured from any account. Change the minimum gap to 20 and watch which ceiling starts binding.
Every line of the arithmetic, so you can check it
Nothing here is proprietary. It is division, and the useful part is knowing which two numbers to divide.
| Step | How it is worked out |
|---|---|
| Slots per mailbox | sending window in minutes, divided by the minimum gap, rounded down |
| Effective sends per mailbox | the lower of that and your configured daily limit |
| Sends the fleet can place | mailboxes multiplied by effective sends per mailbox |
| Sustainable new leads a day | sends the fleet can place, divided by the number of steps, rounded down |
| Days to steady state | steps minus one, multiplied by the days between steps |
| Days of runway | list size divided by sustainable new leads, rounded up |
Rounded down everywhere except runway, which rounds up: reporting 41 days for a list that lasts 41 and two thirds would have it run out mid-morning on a day you had planned to be sending.
Three things this is not
Questions about the numbers
Straight answers. If yours isn't here, ask it on the call: we'd rather tell you no than sell you the wrong thing.
Why is the sustainable number so much lower than my send volume?
What is the spacing ceiling?
What actually breaks if I add leads faster than this?
Does this account for bounces, replies or deliverability?
Are these numbers from your campaigns?
Can I have this as a Claude skill instead?
The same arithmetic is published as a free Claude skill, which adds the diagnosis of a campaign that has already stalled. Whether you may email a given UK prospect at all is a separate check. What we do for money is run the campaigns.