Free Tool · Interactive

Promotion Break-Even Calculator

Before you move a price, find out what the move has to produce just to hold your profit flat. A cut needs extra volume. An increase can afford to lose some. Enter your numbers below and the answer updates as you type. Nothing is sent anywhere, the maths runs in your browser.

Your Numbers
What one unit sells for today, before any discount.
The variable cost of making or buying one unit. Leave out fixed overheads.
Roughly what you sell without a promotion.
Sets the time frame for the dollar figures.
A cut asks how much more you have to sell. An increase asks how much you can afford to lose.
How far you plan to cut the price, as a percentage.
If you have a view on the lift, add it and you will get the profit impact in dollars.
Reset to example numbers
The break-even lift
60% more units

You need to sell 60% more units just to break even.

Add an expected volume increase on the left and this panel will show whether the promotion makes or loses money, and how much, for the period you chose.
Break-even curve
Break-even curve for a 40% marginFor each price change, the volume change that leaves profit where it was. Above the curve profit rises; below it, profit falls. At your 15% cut, volume has to rise 60% to keep profit where it was.−30%−20%−10%0%+10%+20%−50%0%+50%+100%+150%+200%Volume changePrice changeBreak-even curve for a 40% marginFor each price change, the volume change that leaves profit where it was. Above the curve profit rises; below it, profit falls. At your 15% cut, volume has to rise 60% to keep profit where it was.−20%0%+20%−50%0%+50%+100%+150%+200%Volume changePrice change
  • Profit rises
  • Profit falls
  • Break-even
Where the leverage comes from
Price before, and after the discount $100.00 to $85.00
Contribution margin per unit, before $40.00
Contribution margin per unit, after $25.00
Contribution margin %, before and after 40% to 29.4%
Margin per unit before$40.00
Margin per unit after$25.00

The thinking behind this tool: The Promotion That Grew Sales and Shrank Profit →
It explains why the required lift is almost always larger than people expect, and the four mistakes that hide it.

One product is arithmetic. A full portfolio is a different problem: break-even thresholds interact with mix, capacity, and how competitors respond. Start a conversation →