Break-Even Calculator: How Many Units Before You Profit
Itemise your fixed costs — rent, salaries, software, insurance — add your price and variable cost per unit, and see exactly how many you need to sell before the business stops losing money. Plus break-even revenue, contribution margin, the volume for a target profit, your margin of safety, and what happens if price or cost moves. Nothing is uploaded.
Fixed costs
$0 per monthCosts you pay whether you sell one unit or a thousand. Anything that scales with each sale belongs in the variable cost box instead.
Per-unit economics
Add a price to see your break-even point
Enter a selling price per unit to get a break-even point.
Single-product model, tax excluded. Saved on this device only — nothing is uploaded. Business information, not accounting advice.
TL;DR
Break-even is fixed costs divided by the contribution each sale makes. Contribution is price minus the variable cost of that one unit — not your total costs, and not your gross margin from last year’s accounts. Two things decide whether your answer is worth anything: splitting fixed from variable correctly, and being honest about the fixed side, which is why this calculator makes you list each cost rather than type one number you half-remember. Units always round up, because a fraction of a sale does not pay the rent. And the break-even point moves much faster than people expect: on a thin margin, a 10% rise in one input can add anything from single digits on a fat margin to thousands on a thin one to the target.
The one number the whole model turns on
Every sale you make does two jobs. First it pays for itself — the materials, the packaging, the card fee, the courier. Whatever is left over does the second job: chipping away at the costs that were there before the sale happened and would be there without it. That leftover is the contribution per unit, and break-even is simply the point where enough of those leftovers have piled up to cover the fixed costs entirely.
That framing matters because it explains the one thing beginners find counter-intuitive: discounting to sell more volume can push break-even further away, not closer. Cutting the price takes the cut straight out of the contribution, since the variable cost does not fall with it. Drop a price by a tenth on a product where contribution is a third of the price, and you have just removed roughly 30% of the contribution — which means you now need roughly 43% more sales to stand still. The sensitivity table in the tool shows this for your own figures.
break-even units = fixed costs ÷ contribution per unit
break-even revenue = break-even units × price
units for target profit = (fixed costs + target profit) ÷ contribution per unit
margin of safety % = (expected − break-even) ÷ expected × 100
The contribution margin ratio— contribution divided by price — is the same idea expressed as a percentage, and it is the quickest way to compare two products that sell at different prices. It is also the number that tells you what share of every extra pound or dollar of revenue reaches the bottom line once fixed costs are covered.
Sorting your costs, including the awkward ones
The split is the whole game. Put a variable cost on the fixed side and your break-even volume is overstated at low volumes and understated at high ones; do the reverse and the number is quietly optimistic. The test is a single question: if I sold one more unit tomorrow, would this cost go up? If yes, it is variable. If it would sit there unchanged through a month with no sales at all, it is fixed. Here is where the usual costs land, and the ones that refuse to sit on either side.
| Cost | Treat as | Watch out for |
|---|---|---|
| Rent or a unit lease | Fixed | Unchanged whether you sell nothing or sell out. |
| Salaried staff | Fixed | Salary is fixed; overtime and per-job bonuses are not. |
| Software subscriptions | Fixed | Becomes mixed once the plan charges per seat or per transaction. |
| Insurance and accounting fees | Fixed | Annual figures should be divided by twelve for a monthly model. |
| Materials and ingredients | Variable | The clearest variable cost — no unit, no spend. |
| Packaging and shipping | Variable | Easy to forget, and often larger per unit than the materials. |
| Card and payment-gateway fees | Variable | A percentage of price, so it rises when you raise the price. |
| Sales commission | Variable | Only paid on a sale, so it belongs in the per-unit cost. |
| Hourly or freelance labour | Variable | Variable when booked per job, fixed when on a retainer. |
| Utilities | Mixed | A standing charge plus usage. Split it, or treat the base as fixed. |
| Delivery vehicle | Mixed | Lease and insurance fixed; fuel and wear per delivery variable. |
| Marketing | Mixed | A retainer is fixed; per-click or per-order ad spend is variable. |
For the mixed ones, the practical approach is to split them: the standing charge and the lease go in the fixed itemiser, the usage-based part goes into the variable cost per unit. If you cannot separate them cleanly, put the whole thing in fixed costs. That makes your break-even target slightly conservative, which is the direction you want to be wrong in.
Why this one makes you list every fixed cost
Almost every break-even calculator online asks for “total fixed costs” in a single box. That box is where the error lives. People remember rent and wages, and then forget the accountant, the insurance renewal, the four software subscriptions, the business rates, the equipment lease and the loan repayment. Each one is small; together they routinely add a quarter or more to the figure, and every one of them raises the number of units you actually need to sell.
So this calculator gives you a list instead of a box. Add rows, name them, and the total is built in front of you — with one-tap chips for the costs people most often miss. The list is saved in your browser, so next month you update two numbers rather than rebuilding the whole thing from memory.
The period toggle matters too. Per month answers “how many do I need to sell each month to keep the doors open?”. One-off / projectanswers a different question — how many units it takes to pay back a launch, a piece of equipment, a market stall or a print run. The arithmetic is identical; only the period the answer belongs to changes. Just do not mix them: a monthly fixed-cost list with an annual sales target will be out by a factor of twelve.
Break-even moves faster than you think
This is the part most calculators skip, and it is the part that changes decisions. Because contribution sits in the denominator, a small move in price or cost has a leveraged effect on the volume you need. The thinner the margin, the more violent the swing. The table below holds fixed costs at an illustrative 10,000and a price of 100, and varies only the contribution margin — the last column shows what a 10% rise in the variable cost alone does to the break-even volume. These are worked examples for illustration, not figures observed in any particular industry.
| Margin ratio | Contribution | Units to break even | Revenue | If cost +10% |
|---|---|---|---|---|
| 70% | 70 | 143 | 14,300 | +7 |
| 50% | 50 | 200 | 20,000 | +23 |
| 35% | 35 | 286 | 28,600 | +65 |
| 20% | 20 | 500 | 50,000 | +334 |
| 10% | 10 | 1,000 | 1,00,000 | +9,000 |
Read down the last column and the asymmetry is obvious. At a healthy margin, a supplier putting costs up by a tenth is an annoyance. At a thin one it is an emergency, because the same percentage rise eats a far larger share of a far smaller contribution. That is the real argument for protecting margin rather than chasing volume — and the reason the tool gives you the full ±5, ±10 and ±20% grid for both price and cost on your own numbers.
Past break-even: target profit and the safety cushion
Breaking even is not the goal, it is the floor. The useful question is usually “how many do I need to sell to actually take something home?”. Treat the profit you want as though it were one more fixed cost and the same formula answers it: add it to the fixed total and divide again. Every unit past break-even delivers its full contribution as profit, which is why the second half of a good month feels so different from the first.
The mirror image is the margin of safety: the distance between what you expect to sell and what you must sell. Expressed as a percentage it is a plain-English risk measure — “sales can fall by this much before I am losing money.” A wide margin means you can absorb a quiet month, a lost client or a price rise from a supplier. A narrow one means your plan has no slack in it, and it is worth knowing that before you sign a longer lease or add a salary to the fixed list.
If some of your fixed costs are loan repayments, it is worth seeing how the schedule behaves before you commit — the loan calculator breaks a repayment into interest and principal, and the emergency fund calculator applies the same “how many months can I survive” logic to personal finances.
Where this model stops being true
Break-even analysis is a straight-line model, and reality is not a straight line. Four honest caveats. Product mix: this assumes one product at one price; if you sell several, either run it per product or use a weighted average contribution, and re-run it when the mix shifts, because a month that sells more of your thin-margin line breaks even later even at identical revenue. Step-fixed costs: fixed costs stay flat only within a range. Pass a certain volume and you need a second van, a bigger unit or another pair of hands, and the break-even point jumps to a new, higher plateau.
Tax: nothing here is tax-adjusted. A target profit you enter is a pre-tax figure, so if you need a specific amount after tax you will have to gross it up yourself, using the rates that apply to your own business and jurisdiction. Timing: breaking even on paper and having money in the bank are different things. Sales on 30-day terms, stock bought in advance and seasonal swings all mean a business can be past break-even and still short of cash. Break-even tells you whether the model works; a cash-flow forecast tells you whether you survive until it does.
None of that makes the number useless — it makes it a benchmark rather than a promise. Used properly it answers real questions quickly: whether a price is high enough, whether a new fixed cost is affordable, how much of a discount you can survive, and how far your plan sits from the edge.
Frequently asked questions
How do you calculate the break-even point?
Subtract the variable cost of one unit from its selling price to get the contribution per unit — the amount each sale puts toward your fixed costs. Then divide total fixed costs by that contribution. Fixed costs of 12,000 with a contribution of 30 per unit means 12,000 ÷ 30 = 400 units to break even. Multiply that by the price to get break-even revenue. The same formula works whether you are measuring a month, a quarter or a single project, as long as the fixed costs and the sales volume cover the same period.
What counts as a fixed cost and what counts as a variable cost?
A fixed cost is one you pay whether you sell nothing or sell out: rent, salaried staff, software subscriptions, insurance, accounting fees, equipment leases. A variable cost only exists because a particular unit was made or sold: materials, packaging, shipping, payment processing fees, per-unit commission, the hourly cost of a contractor on that job. The test is whether the cost changes when volume changes. Getting this split wrong is the most common reason a break-even figure is misleading, and it is why this calculator makes you itemise the fixed side rather than asking for a single guessed total.
Why does the calculator round break-even units up?
Because you cannot sell part of a unit and be paid for it. If the exact arithmetic says 412.3 units, selling 412 leaves a slice of fixed cost uncovered — you are still fractionally in the red. Rounding up to 413 is the first whole unit at which you are genuinely not losing money, so it is the honest answer to the question people are asking. The tool shows the exact unrounded figure alongside it so you can see how close the two are, and the small surplus that the rounding creates.
What does it mean if there is no break-even point?
It means your contribution per unit is zero or negative — the price is at or below the variable cost of delivering the unit. At exactly zero, every sale covers its own cost and contributes nothing to rent or salaries, so no volume ever covers your fixed costs. Below zero, each sale actively loses money and more volume makes the loss bigger, not smaller. There is no sales target that fixes this; the price has to rise, the variable cost has to fall, or the product has to change. The calculator says so explicitly rather than showing an infinite or negative unit count.
What is the margin of safety and what is a healthy number?
The margin of safety is how far your expected sales sit above break-even, expressed in units, in revenue and as a percentage: (expected − break-even) ÷ expected × 100. A 40% margin of safety means sales could drop by 40% before you stop covering costs. There is no universal safe threshold, but the lower the figure the more a quiet month hurts, and a margin in single digits means you are one lost customer or one supplier price rise away from a loss. Seasonal businesses usually want a wide margin in the good months to carry the thin ones.
What does this break-even calculator leave out?
It is a single-product contribution-margin model, which is the standard textbook one, and it deliberately excludes several real-world complications. Tax is not modelled, so a target profit is a pre-tax figure. It assumes one product with one price and one variable cost, whereas most businesses have a mix whose average margin shifts with what actually sells. It assumes fixed costs stay flat, whereas in reality they step up — a second van, a bigger unit, another hire. And it ignores the timing gap between making a sale and being paid for it. Treat the answer as a planning benchmark, not a cash-flow forecast.
This calculator provides general business information using the standard contribution-margin break-even model. It is not accounting, tax or financial advice, it does not know your full circumstances, and any example figures on this page are illustrative rather than observed market rates. Results are only as accurate as the costs and prices you enter — check anything material with a qualified accountant before acting on it.