Break-even and margin: how much do you actually need to sell?
More sales do not necessarily mean a business covers its costs. First ask what remains from each sale to pay fixed expenses. That contribution, rather than revenue alone, drives the break-even calculation.
Align the period and separate the costs
Use one period, such as a month. Fixed costs apply within the assumed activity range; variable costs move with sales or production. Split a bill containing both a subscription and a per-order charge.
Contribution per unit equals selling price minus variable cost per unit. Break-even units equal fixed costs divided by that contribution. This is a planning estimate, not proof of market demand or a guarantee of profit.
References: U.S. Small Business Administration — Break-Even Point · OpenStax — Calculate a Break-Even Point in Units and Dollars
Margin and markup use different denominators
A product costs 60 and sells for 100, leaving a difference of 40. Markup is 40 ÷ 60, approximately 66.67%. Margin relative to sales is 40 ÷ 100 = 40%. An instruction to “add 40%” is ambiguous unless the base is clear.
Contribution is not net profit: fixed and other expenses have not yet been deducted.
When the estimate becomes misleading
If contribution is zero or negative, more volume alone will not cover fixed costs in this model. Recalculate when the sales mix, price or service cost changes.
Include applicable packaging, commissions and returns without counting the same expense twice. Handle taxes according to the relevant records and rules. The example below is simplified arithmetic, not tax advice.
Original example: a daily target for a small shop
Monthly fixed costs are 12,000 and variable costs are 40% of sales. The contribution ratio is 60%, so monthly break-even sales are 12,000 ÷ 0.6 = 20,000.
Across 25 working days, the average target is 800 per day. At 100 per order, that is an average of 8 orders daily. This describes a mathematical target, not evenly distributed or guaranteed demand.