Elastic: above 1
Units change by more than the price. A lower price raises revenue and a higher price lowers it. Decision: whether a price cut can win enough extra units to pay.
Enter two prices and the units you sold at each. The calculator gives the price elasticity of demand by the midpoint (arc) method or the simple percentage method, says whether demand is elastic, unit elastic or inelastic, and shows what the price change did to revenue and, with a unit cost, to profit.
Berend Vrakking, founder. Last updated .
Your results
Elastic: units changed by more than the price did, so revenue moves opposite to the price.
Revenue rose by €400.00 (+8.0%).
Revenue effect
Profit effect
Profit-maximising price
€142.50
Unit cost × e ÷ (e − 1), where e is the absolute elasticity
If demand keeps this elasticity at every price, profit is highest at €142.50: the unit cost times 2.375. That is outside the €90.00 to €100.00 you entered, so it extrapolates beyond your data.
Assumes demand keeps this elasticity at every price and your unit cost stays constant.
Elasticity compares units sold at two prices. Anything else that changed between the two periods (season, stock, ads, competitor prices) is in the number too.
The start values are illustrative data.
How it works
Illustrative data. A shop lowered a product from €100.00 to €90.00. It sold 50 units at the old price and 60 units at the new price. One unit costs €60.00.
| Step | Calculation | Result |
|---|---|---|
| Change in units (midpoint) | (60 − 50) ÷ ((50 + 60) ÷ 2) | +18.18% |
| Change in price (midpoint) | (€90.00 − €100.00) ÷ ((€100.00 + €90.00) ÷ 2) | -10.53% |
| Elasticity | +18.18% ÷ -10.53% | -1.73 |
| Demand is | 1.73 is above 1 | Elastic |
| Elasticity (simple method) | +20.00% ÷ -10.00% | -2.00 |
| Revenue before | €100.00 × 50 | €5,000.00 |
| Revenue after | €90.00 × 60 | €5,400.00 |
| Revenue change | €5,400.00 − €5,000.00 | +€400.00 (+8.0%) |
| Profit before | (€100.00 − €60.00) × 50 | €2,000.00 |
| Profit after | (€90.00 − €60.00) × 60 | €1,800.00 |
| Profit change | €1,800.00 − €2,000.00 | -€200.00 (-10.0%) |
| Units needed to keep the old profit | €2,000.00 ÷ (€90.00 − €60.00) | 66.7 |
Demand is elastic, so the cut raised revenue by €400.00. Profit still fell by €200.00: each unit now earns €30.00 instead of €40.00, and 60 units fall short of the 66.7 needed to keep the old profit. Elasticity says how units respond. Your margin decides whether the response pays.
What the result means
Units change by more than the price. A lower price raises revenue and a higher price lowers it. Decision: whether a price cut can win enough extra units to pay.
Units change by as much as the price, so revenue stays the same. Decision: none from revenue alone; read profit.
Units change by less than the price. A higher price raises revenue and a lower price lowers it. Decision: whether a price rise is worth the units you lose.
Elasticity is normally negative: a higher price sells fewer units. Read the absolute value for the class. A positive value means something besides the price moved the units.
Revenue can rise while profit falls. Enter a unit cost to see both, and the units a new price needs to keep your profit.
The midpoint method divides by the average of old and new, so direction does not matter. The simple method divides by the old value. For small changes they agree; for large ones they do not.
Profit-maximising price
If demand has the same elasticity at every price and your unit cost is constant, profit is highest at a price of unit cost × e ÷ (e − 1). Here e is the absolute elasticity, and it must be above 1. This is a reference point from a model, not a forecast.
Profit is (price − cost) × units. With units falling as a constant power of the price, its slope is zero where price − cost equals price ÷ e. Rearranged, that is price = cost × e ÷ (e − 1).
Illustrative data. With e = 1.7273 and a unit cost of €60.00, the price is €60.00 × 1.7273 ÷ (1.7273 − 1) = €60.00 × 2.375 = €142.50.
Under this assumption profit keeps rising with the price, so there is no highest point. Real demand drops off at some price, and this model cannot find it.
Elasticity measured between €90.00 and €100.00 says little about €142.50. It also changes with season, stock, ad spend and competitor prices. Change prices in small steps and measure again.
Competitor prices
This calculator measures how your units respond to your own price. How your units respond to a competitor’s price is cross-price elasticity: % change in your units ÷ % change in their price. A positive value means the products are substitutes.
Competitor Prices in Product Metrics shows your price position against comparable competitor products. It makes no price recommendations and does not measure elasticity.
Limits
Two periods give one number, and every change in between is in it: season, stock, ads, promotions and competitor prices. Change one product at a time and compare periods of equal length.
Elasticity from two prices describes that range only. It is not a demand curve.
Elasticity belongs to one product. A shop-wide figure describes none of its products.
A few sales per week make the number noisy. Treat a result from low volumes as a hint, not a measurement.
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