How much volume can a price rise afford to lose?
A price increase lands entirely on contribution margin, because variable costs do not move with the price. This calculator takes your current price, your contribution margin per unit and the price change you are weighing, and returns the new margin per unit, the volume you could lose before total margin falls below today, and the verdict at your own volume estimate.
The unit's selling price today. Works per SKU, or use AOV for a storewide move.
Margin before marketing: price minus discounts, landed COGS (cost plus freight-in plus duty), shipping and fulfilment, and payment and platform fees. Compute it with the contribution margin calculator.
The move you are weighing. Positive for a rise, negative for a cut.
Your estimate of how unit volume responds. Negative for a loss, positive for a gain. Leave it blank to just read the headroom.
A +10.0% move lifts contribution from $40.00 to $50.00 per unit. You can lose up to 20.0% of unit volume and still keep every dollar of today's total margin.
Break-even volume at each move: the unit volume, as a multiple of today's, at which total margin equals today's. Below 1.00x the move can absorb a volume loss; above 1.00x it must win a gain. Computed from your inputs, nothing assumed.
Four numbers in, one verdict out
Pull the current price
From your price list or store catalog. Model one SKU at its own price for a single reprice, or use AOV from your store admin if the whole store moves: the ratios hold either way.
Pull the margin per unit
From the contribution margin calculator or your ledger: price minus discounts, landed COGS (cost plus freight-in plus duty), shipping and fulfilment, and payment and platform fees. Toggle to % if you know the ratio instead.
Enter the move
From the pricing review, the supplier cost letter that forced the question, or the draft reprice. Positive for a rise, negative for a cut: the math flips sign correctly.
Read the headroom
The tolerable volume loss is the number to beat, not a prediction. If you have a volume estimate from a past reprice in your order history, add it and read the total-margin verdict too.
The move lands on margin, not on revenue
Landed COGS, shipping and fulfilment are attached to the unit, not to the sticker. Move the price and those costs stay where they are, so every dollar of the change passes straight through to contribution margin. The volume math follows from that single fact.
Same definitions as The Math: the margin here is contribution margin before marketing. The model holds the variable costs flat while the price moves, which is exactly why the whole change lands on margin. The loss and gain thresholds hold total contribution margin equal to today's; they need the new CM above zero, and the tolerable loss additionally needs the move to be a rise.
At a price of $100.00 with $40.00 of contribution per unit before marketing, a +10.0% move changes the price by +$10.00. Landed COGS and fulfilment stay attached to the unit, so the whole change lands on margin: the new contribution is $40.00 + $10.00 = $50.00 per unit.
Each remaining unit now carries more margin, so total margin holds flat at $40.00 ÷ $50.00 = 0.80x of today's unit volume. That is the headroom: up to 20.0% of volume can walk before the move costs you a single dollar of total margin.
At your estimate of -10.0% volume, total margin changes by (1 − 10.0%) × $50.00 ÷ $40.00 − 1 = +12.5%. The move ends ahead of today.
These are your live inputs from the calculator above, not a canned example. Change a number up there and this paragraph follows.
The pass mark for every reprice
Operators fear price rises far beyond the math. The tolerable volume loss puts a number on the fear before the decision is made, and it usually says the rise is far cheaper than the room believes.
Price with arithmetic, not fear
At a 40% contribution margin, a +10% rise keeps every dollar of total margin even if a fifth of the volume walks: that is your own calculator output, not a benchmark. Run the number before the meeting where the rise gets talked down.
Set the pass mark before the move
Write the tolerable loss next to the reprice before it ships. Thirty days later the comparison is a fact, not a feeling: volume inside the headroom means the rise paid, volume beyond it means the move needs revisiting.
Know when a cut can pay
A cut needs a computed volume gain, not a volume hope. If the required gain is bigger than any lift a past reprice or promotion actually produced, the cut buys revenue with your margin: restructure the offer instead.
Honest about what arithmetic cannot predict
This calculator is the right first check on any reprice: it prices the headroom in seconds and reframes the fear as a threshold. But it computes what the move can afford, not what the market will do, and it is worth being honest about the difference.
The headroom is not a forecast
The tolerable loss is the threshold the move has to stay inside, not a prediction of what volume does. The actual response is elasticity, it differs by product, segment and season, and reading the headroom as a forecast is exactly the gut-feel trap.
One blended unit
A reprice never lands evenly. Margins differ by SKU, so the same +10% buys different headroom on a hero product and a slow mover. Run each SKU's move against that SKU's own margin: a blended unit can only give a blended answer.
It prices the move, not the market
Competitor response, discount overlap and who the new price attracts or repels all sit outside the arithmetic. A rise that holds volume but shifts the mix toward discounted orders can still cost margin this page never saw.
Test the move against real demand
This page tells you the volume a price move can afford to lose. It cannot tell you the volume the move will actually cost: that is elasticity, and gut feel is the wrong instrument for it. Blufire S11 Planning & Forecasting runs the Scenario Lab, COGS, AOV and discount what-ifs tested against your forecast, and S12 Financial Models includes price elasticity modeling, so a reprice is checked against real demand data before you commit.
When to run it, and what triggers action
Questions operators ask
Because the variable costs are attached to the unit, not to the price. Landed COGS (cost plus freight-in plus duty) and shipping and fulfilment cost the same whether the unit sells for $100 or $110, so when the price moves and those costs stay put, every dollar of the change passes straight through to contribution margin per unit.
Because each remaining unit carries more margin. At a $100 price and $40 contribution margin, a +10% rise lifts each unit's contribution to $50, so 80% of today's volume at $50 per unit carries exactly the total margin that 100% carried at $40. That is the iso-margin point: 1 minus 40 divided by 50 is a 20% tolerable volume loss.
Yes, with the sign flipped. A cut comes straight out of margin the same way a rise adds to it, so instead of a tolerable loss the calculator returns the volume gain the cut must win just to hold total margin flat. And once the cut is as deep as your contribution margin, no volume can pay for it: each extra unit digs the hole deeper.
Economically they draw from the same margin pool; the difference is scope and permanence. A code is temporary, targeted and lands only on redeemed orders, so it is priced per promotion with the discount impact calculator. A reprice moves every future order until you move it back, which is why it deserves this calculator's iso-margin test before it ships.
The contribution margin before marketing of what is actually being repriced: price minus discounts, landed COGS (cost plus freight-in plus duty), shipping and fulfilment, and payment and platform fees. Use the SKU's own margin for a single reprice rather than the store-wide blend, and compute it with the contribution margin calculator if you do not have it to hand.
No. It is the threshold the move has to stay inside, computed from your margin alone. What volume actually does after a reprice is elasticity, and that depends on your demand, your competitors and your customers, none of which this page can see. Treat the headroom as the pass mark, and test the move against real demand data before committing.