The job this tool does, and who does it today
Somebody in the business asks a simple question before a festival campaign: what will it cost to message our customers on WhatsApp? The answer is rarely simple, because the cost depends on how many contacts are genuinely reachable, which template category the message falls into, what your provider charges, and how many people reply.
Today that estimate is usually produced by multiplying the size of a contact spreadsheet by a rate somebody read in a blog post. The result is wrong twice over: too high because a large share of the list is not reachable, and too low because the platform fee and the replies were never counted.
A broadcast cost calculator's job is to give a marketing or sales lead a defensible number before the campaign, and a cost per reply after it.