Formula
Contribution per unit = selling price − variable cost. Break-even units equal fixed costs divided by contribution per unit. Round units up because a partial sale normally cannot cover the remaining cost.
Free break-even calculator
How many sales do you need to break even?
Calculate break-even units and revenue from fixed costs, selling price, and variable cost per unit.
How the calculation works
Use consistent inputs and keep the result in context.
What belongs in fixed cost?
Include costs that do not change directly with each sale during the period: rent, base payroll, core software, insurance, and recurring professional fees. Keep owner drawings and tax treatment separate unless they are part of the planning question.
What belongs in variable cost?
Include the cost created by one additional sale: product cost, packaging, transaction fee, sales commission, fulfillment, and usage-based service cost. Use the same time period and currency for every input.
Continue planning
Connect the number to the operating decision.
Use the result as a starting estimate, document the assumptions, and replace them with actual records as the business operates.