The working behind the answer
How to use this calculator
Enter a constant unit cost, original price, proposed discount and baseline sales volume. The calculator compares contribution per unit and shows the discounted margin when the discounted price is positive. A preservation target is shown when both profit figures are positive.
The formula
Compare a discount
New price = price × (1 − discount ÷ 100); profit per unit = price − cost
A worked example
An item costing £60 and selling for £100 contributes £40. A 20% discount reduces the price to £80 and contribution to £20. You need 20 discounted sales to match the contribution of 10 full-price sales.
Good to know
This does not forecast how customers respond to a discount. It assumes unit cost stays constant as volume changes. At a zero selling price, margin is undefined. A non-positive discounted contribution cannot preserve positive original contribution by selling more.
Common questions
Does a 20% discount reduce profit by only 20%?
Not usually. Costs remain, so profit can fall by a larger proportion than the selling price.
Is the required volume a demand forecast?
No. It is the arithmetic volume required under the entered cost and price assumptions.