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Contribution Margin Formula

Contribution margin is the revenue left after variable costs. It is available to cover fixed costs and then operating profit.

Sales revenue − Variable costsChange the sample figures

Calculated result$100,000.00

Calculated from the sample figures using the displayed formula.

What is the contribution margin formula?

Contribution Margin FormulaSales revenue − Variable costs

Contribution margin is the revenue left after variable costs. It is available to cover fixed costs and then operating profit.

What do the inputs mean?

Sales revenue
The value entered for sales revenue. Keep its period and units consistent with the other inputs.
Variable costs
The value entered for variable costs. Keep its period and units consistent with the other inputs.

How to calculate it step by step

  1. Define the decision.
    Write down what the result will help you compare or decide.
  2. Collect matching inputs.
    Use figures from the same period and apply the definitions shown on this page.
  3. Apply the formula.
    Sales revenue − Variable costs.
  4. Check the units.
    Confirm whether the result is a currency amount, percentage, number of periods or ratio.
  5. Test a second case.
    Change one assumption at a time to see what drives the result.

Worked example

Using the sample figures in the calculator, the result is $100,000.00. Change one figure at a time and recalculate to see which assumption has the greatest effect. A spreadsheet should return the same result when it uses the same formula, units and timing.

When should you use contribution margin formula?

Use it for pricing, product-mix and break-even decisions.

Limitations and common mistakes

A cost may be fixed in one operating range and variable in another.

Do not mix annual figures with monthly figures, ending balances with averages, or percentages with whole numbers. Record the definition used so another person can reproduce the result.

Frequently asked questions

What is contribution margin formula?

Contribution margin is the revenue left after variable costs. It is available to cover fixed costs and then operating profit.

How should I use contribution margin formula?

Use the formula only after matching every input to the same period, unit and definition. Then compare the result with a worked example and the decision you are trying to make.

What is the most common mistake with contribution margin formula?

A cost may be fixed in one operating range and variable in another.

Can I calculate contribution margin formula in a spreadsheet?

Yes. Reproduce the displayed equation with separate cells for each input, keep percentages as decimals, and test the spreadsheet against the worked example before replacing the sample figures.

Sources and methodology

This page uses the Calculate a Break-Even Point in Units and Dollars for the underlying financial or reporting context. Spreadsheet-related behavior is checked against Microsoft’s financial-function documentation. Examples are illustrative and use the formula displayed on the page.

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