Break-even is the point where a business stops losing money and starts making it. Below it, every day of trading costs you. Above it, every additional sale is profit.

It is the single most useful number in early business planning, and it takes about two minutes to calculate. Most people who have never worked it out are surprised by how far away it is.

The formula

Break-even units equals fixed costs divided by contribution per unit. Contribution per unit is your selling price minus your variable cost per unit.

An example. Your fixed costs are 3,000 a month. You sell at 50 and each unit costs you 20 to produce. Contribution is 30. Divide 3,000 by 30 and you need 100 units a month to break even, which is 5,000 in revenue.

Sell 99 and you lose money. Sell 101 and you make 30. That is the entire concept, and our break-even calculator does the arithmetic including your margin of safety.

Sorting your costs correctly

This is where the calculation actually goes wrong, and it goes wrong quietly. The formula is trivial; classifying the inputs is the real work.

Fixed costs do not change with how much you sell. Rent, salaries, software subscriptions, insurance, accounting fees. You pay them whether you sell nothing or a thousand units.

Variable costs scale with each sale. Materials, manufacturing, packaging, shipping, payment processing fees, sales commission.

Three costs are routinely misclassified:

• Advertising. If you spend more to sell more, it behaves as a variable cost and belongs in the per-unit figure. Treating a scaling ad budget as fixed makes break-even look far closer than it is.
• Payment processing. A few percent of every transaction. Small enough to forget, large enough to matter on thin margins.
• Your own time. If you are not paying yourself, your break-even is artificially low. Include a realistic salary for yourself or you are calculating the break-even of a hobby.

Margin of safety

Once you are past break-even, this is the number worth watching. It tells you how far sales could fall before you drop back into loss.

Break even at 100 units and sell 105, and you are technically profitable and extremely fragile. One slow month erases it. Break even at 100 and sell 200, and you have a 50% margin of safety — room to absorb a bad quarter, a lost client, or a supplier price rise.

Both businesses report a profit. They are in completely different positions, and the profit figure alone does not reveal that.

Two ways to lower break-even

Raise contribution per unit. Increase price or reduce unit cost. This is the leveraged option, because it changes the denominator. A 10% price rise on a product with a 40% contribution margin lowers your break-even volume by roughly a fifth.

Cut fixed costs. Direct and immediate, but bounded — there is a floor below which the business cannot operate, and cutting into it usually costs you capacity.

Price increases are the fastest lever and the most resisted. Most owners assume a price rise loses customers proportionally. It rarely does, and the arithmetic means you can lose a meaningful share of volume and still be better off.

Break-even in revenue rather than units

If you do not sell discrete units — a consultancy, an agency, a subscription business — units are awkward. Calculate in revenue instead.

Divide your fixed costs by your contribution margin expressed as a decimal. If your contribution margin is 60% and your fixed costs are 3,000, then 3,000 divided by 0.6 gives 5,000 in revenue needed. Same answer as the unit method, expressed in a form that works for any business.

This version is also easier to sanity-check against reality, because most owners know roughly what they turn over in a month even if they have never counted units.

Break-even on a single campaign or product launch

The same logic applies to a one-off investment, and this is where it gets genuinely useful for decision-making rather than reporting.

Spending 2,000 developing a new product with a contribution of 25 per sale means 80 sales to recover the investment. Whether that is sensible depends on how long it takes — 80 sales in a month is a good decision, 80 sales over three years is dead capital.

Advertising has its own version of this, and it is the one most businesses get wrong. Your break-even ROAS is 100 divided by your gross margin percentage. At a 60% margin you need 1.67 times your spend back just to stand still. At 25%, you need 4 times. A campaign returning 3x looks excellent and loses money on a thin margin, which is exactly what our ROAS simulator exists to show.

Why discounting is more expensive than it looks

Break-even makes the true cost of a discount obvious, and it is much higher than most people assume.

Take the earlier example: price 50, variable cost 20, contribution 30, break-even 100 units. Offer a 20% discount and the price drops to 40, contribution falls to 20, and break-even rises to 150 units. A 20% price cut requires a 50% increase in volume just to stay where you were.

Run that calculation before every sale or promotion. Most discounts, examined this way, need a volume increase the business has no realistic way of achieving.

When break-even analysis misleads

The model assumes a lot, and knowing what it assumes stops you trusting it further than it deserves.

• It assumes one price. Discounts, tiers and bulk pricing all break the single-contribution figure. Use a weighted average across your actual sales mix.
• It assumes costs stay linear. They do not. Suppliers give volume discounts, and at some point you need another employee or a bigger space, which steps your fixed costs up sharply.
• It ignores timing. Break-even is monthly; cash flow is daily. A business can be above break-even on paper and still fail because customers pay in sixty days and suppliers want thirty.
• It says nothing about demand. The calculation tells you how many units you need. It has no opinion on whether anyone will buy them.

That last point is the one that matters most. Break-even tells you what is required, not what is achievable. If the number comes out at 400 units a month and your market realistically buys 50, the answer is not to sell harder — it is that the model does not work at that price.

Using it before you start

The most valuable time to run this calculation is before committing money, because it converts an idea into a testable claim.

1. List every fixed cost for a month, including paying yourself.
2. Work out your true variable cost per unit, including processing fees.
3. Set a price you believe the market will accept.
4. Calculate the units needed.
5. Ask honestly whether you can sell that many, every month.

If step five makes you uncomfortable, you have learned something important for the cost of five minutes rather than five months. Either the price is too low, the costs are too high, or the idea needs rethinking.

Frequently asked questions

What is a good break-even point?

There is no universal figure. What matters is whether it sits comfortably below your realistic sales volume. A break-even at 30% of expected sales is healthy; one at 90% leaves no room for a bad month.

How do I calculate it for a service business?

Treat billable hours or projects as your units. Contribution is your rate minus any direct delivery cost. If you have almost no variable costs, break-even is simply fixed costs divided by your rate — which is close to what our freelance rate calculator works out from the other direction.

Should I include tax?

Standard break-even is calculated before tax, since tax applies to profit. If you want the volume needed for a specific after-tax income, gross the target up before adding it to fixed costs.

What if I sell several different products?

Use a weighted average contribution based on your actual sales mix. Recalculate when the mix shifts, because selling more of a low-margin product raises your break-even even if total revenue rises.

The number to know by heart

Most small business owners cannot state their break-even point from memory. It is the number that tells you whether this month was survival or progress, and it should be as familiar as your rent.

Work it out once, write it somewhere visible, and recalculate whenever your costs or prices change. Then run the scenarios — what a 10% price rise does, what hiring someone does, what a supplier increase does. Those answers are what turn the number into a decision-making tool rather than a statistic.