Showback Calculator

reported cost = direct cost + shared pool × reporting share; cost per unit = reported cost ÷ units served; change% = (reported cost − prior month) ÷ prior month. Showback uses exactly the same allocation arithmetic as chargeback but stops before the money moves, so the shared platform layer is attributed for visibility while the central team keeps the invoice. Because nothing is being billed, the useful outputs are the trend and the cost per unit rather than the absolute figure — those are what a team can act on.

Showback is how most organisations start, since it surfaces every allocation argument while the stakes are still low and gives teams a number they recognise before it appears in their budget. Publish the reporting key alongside the number or the conversation becomes about the method instead of the cost.

This calculator takes 10 inputs: Team A direct cost, Team B direct cost, Team C direct cost, Shared platform cost reported alongside, Shared-cost reporting key, Team A weight, Team B weight, Team C weight, Team A billable units served, Team A reported cost last month. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.

Reliably yes, provided the report reaches the engineers rather than only their director, and provided it carries a unit cost rather than a raw total. Teams optimise what they can see attributed to their own service; what they cannot see they assume belongs to somebody else.