Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Break-even units per month
215
Break-even revenue
$16,985
Contribution margin per unit
$56.00
Contribution margin
70.9%
Units to hit your profit target
304
Units per day
7.2
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How to use this
- 1Enter fixed costs per month ($).
- 2Enter price per unit ($).
- 3Enter variable cost per unit ($).
- 4Enter target monthly profit ($).
- 5Read your break-even units per month on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
Break-even is where contribution margin finally covers fixed costs. The lever most owners miss is price: a 10% price rise cuts the break-even volume far faster than a 10% cost cut.
Worked example
Using the values the calculator loads with:
Inputs
- Fixed costs per month: 12000 $
- Price per unit: 79 $
- Variable cost per unit: 23 $
- Target monthly profit: 5000 $
Results
- Break-even units per month: 215
- Break-even revenue: $16,985.00
- Contribution margin per unit: $56.00
- Contribution margin: 70.9%
- Units to hit your profit target: 304
- Units per day: 7.2
What each field means
Inputs
- Fixed costs per month ($)
- The fixed costs per month used in the calculation, measured in $. Starts at 12000 $ so you have a working example on load.
- Price per unit ($)
- The price per unit used in the calculation, measured in $. Starts at 79 $ so you have a working example on load.
- Variable cost per unit ($)
- The variable cost per unit used in the calculation, measured in $. Starts at 23 $ so you have a working example on load.
- Target monthly profit ($)
- The target monthly profit used in the calculation, measured in $. Starts at 5000 $ so you have a working example on load.
Results
- Break-even units per month
- Returned as a whole number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Break-even revenue
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Contribution margin per unit
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Contribution margin
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Units to hit your profit target
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Units per day
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the break-even calculator work?
Break-even is where contribution margin finally covers fixed costs. The lever most owners miss is price: a 10% price rise cuts the break-even volume far faster than a 10% cost cut. The underlying maths is: Break-even units = Fixed costs ÷ (Price − Variable cost per unit).
What do I need to enter?
4 values: fixed costs per month, price per unit, variable cost per unit, and target monthly profit. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the break-even units per month result mean?
It is returned as a whole number and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
Who is this tool for?
It's built for anyone comparing money scenarios before committing — budgeting a payment, sanity-checking a quote, or seeing what a change in rate or term actually costs.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Break-Even Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/break-even
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/break-even" target="_blank" rel="noopener">Break-Even Calculator — RevenueLab</a> (2026).</p>
Source: [Break-Even Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/break-even) (2026).