How this calculation works
A process can create several products before they can be separately identified. Allocating the common joint cost requires a stated basis, and different bases can produce different reported product costs without changing the total joint cost. This page supports relative split-off sales value and relative net realizable value. It exposes each product’s allocation base before distributing the common amount.
Split off base = quantity × split off price; NRV base = final sales − subsequent costs; allocation = joint cost × relative baseA worked example
Product A sells ten units at twenty, less subsequent cost one hundred, giving NRV base one hundred. Product B sells ten at thirty, less one hundred, giving base two hundred. Allocating joint cost three hundred by those bases gives one hundred to A and two hundred to B. Their allocation total is still three hundred, while using split-off sales values would change the proportions.
Good to know
Negative NRV, by-product accounting, physical-unit bases and market-price estimation are not implemented. Prices and later costs remain entered assumptions. The result does not certify accounting-standard compliance or identify which product is economically best. Allocation method and decision purpose need to be documented separately from the arithmetic.
Reference: OpenTuition — joint product allocation (opens in a new tab) ↗
What this calculation answers
A process can create several products before they can be separately identified. Allocating the common joint cost requires a stated basis, and different bases can produce different reported product costs without changing the total joint cost.
This page supports relative split-off sales value and relative net realizable value. It exposes each product’s allocation base before distributing the common amount.
The Activity based costing driver allocation calculator uses activity consumption. A joint-process allocation uses relative product bases and should not be mistaken for a causal driver model.
Use the right input conventions
In split-off mode the entered unit price must be the split-off price. In net-realizable mode it is the final selling price, from which the complete subsequent product cost is subtracted.
Subsequent cost is a product total, not per-unit cost. Every supported allocation base must be nonnegative, and the combined base must be positive for a meaningful relative allocation.
Interpret the result
Allocated joint costs must sum back to the entered common cost. That conservation does not show that the allocation measures a causal cost of producing each product independently.
A sell-or-process-further decision compares incremental revenue and incremental subsequent cost. An allocated share of sunk joint cost should not automatically be treated as avoidable when making that separate decision.
Work through the example
Product A sells ten units at twenty, less subsequent cost one hundred, giving NRV base one hundred. Product B sells ten at thirty, less one hundred, giving base two hundred.
Allocating joint cost three hundred by those bases gives one hundred to A and two hundred to B. Their allocation total is still three hundred, while using split-off sales values would change the proportions.
Where the model stops
Negative NRV, by-product accounting, physical-unit bases and market-price estimation are not implemented. Prices and later costs remain entered assumptions.
The result does not certify accounting-standard compliance or identify which product is economically best. Allocation method and decision purpose need to be documented separately from the arithmetic.
A few questions, answered
Does the product with more allocated cost necessarily cause more joint cost?
No. Relative allocation distributes a common total under a chosen convention and is not a causal cost estimate.
What changes in the comparison?
Use relative entered sales values without subtracting subsequent costs.