How to use this calculator
- Enter pack a price, pack a quantity, pack b price, pack b quantity.
- Choose a display currency, then select Calculate. Results also update after a brief pause while you edit.
- Read the result with the assumptions below. Export details or save a second scenario to compare your choices.
Formula and method
Assumptions and limitations
Convert quantities to the same mass, volume or count unit first. Tax, shipping and unusable remainder are not automatic.
Worked example
With pack a price = 12, pack a quantity = 3, pack b price = 18, pack b quantity = 6, pack a cost per unit is approximately 4.
What the result means
A positive A-minus-B difference means Pack B costs less per unit, before waste or quality differences.
Common questions
How should I interpret pack a cost per unit?
A positive A-minus-B difference means Pack B costs less per unit, before waste or quality differences.
What should I check before using this result?
Convert quantities to the same mass, volume or count unit first. Tax, shipping and unusable remainder are not automatic.
Methodology and transparency
Calculation specification reviewed on 2026-10-14. Mathematical implementation is tested against independent reference fixtures. This does not imply review by a licensed financial professional. Read the testing and precision policy.