Cost Allocation by Usage Calculator

About this calculator

Usage-based cost allocation splits a shared expense between two or more parties in proportion to how much each one actually consumed, rather than splitting it evenly — the allocated share for a party equals (that party's usage ÷ total usage) × total cost. This method is grounded in the same proportional-allocation logic used in cost accounting for assigning shared overhead to different departments or products based on a chosen usage driver, such as machine hours, square footage, or metered consumption.

Roommates splitting a shared electricity bill by metered usage, businesses allocating shared office or equipment costs across departments by actual usage, and property managers dividing utility costs among tenants by submetered consumption all rely on this kind of proportional split, since it is generally seen as fairer than an even split when usage is uneven.

This calculator takes each party's usage amount and the total shared cost and returns exactly what each party owes in proportion to their share of total usage.