Free Business Calculators
Four calculators every owner should run at least once: where you break even, what your margins really are, what a customer is worth, and what one costs to acquire.
107
Break-even sales / mo
$12,800
Break-even revenue / mo
$75
Profit per unit
63%
Contribution margin
The four numbers every owner should know
Break-even tells you the floor: how many sales a month keep the lights on, and how much safety margin you actually have. Profit margin tells you whether your pricing works (gross margin) and whether the whole business works (net margin). Customer lifetime value tells you what a customer is really worth across the relationship - almost always more than one sale. And customer acquisition cost tells you what you pay to win each one. Most pricing, marketing, and hiring decisions get easier once these four are written down.
The LTV:CAC ratio - the one investors check first
Dividing lifetime value by acquisition cost compresses your whole growth model into one number. Below 1:1, every new customer loses money. Around 3:1 is the classic healthy benchmark: acquisition is clearly profitable with room for overhead. Far above 5:1 often means the opposite problem - you are under-investing in growth that would pay for itself. Calculate LTV on profit (revenue times gross margin), not raw revenue, or the ratio flatters you.
Frequently Asked Questions
Divide your fixed monthly costs by your contribution margin per sale (price minus variable cost per unit). Example: $8,000 fixed costs and $75 contribution per sale means 107 sales a month to break even. Everything past that contributes its full margin to profit.
It varies by industry: 10%+ net margin is solid for most service businesses, 5-10% is typical for retail and restaurants, and software runs much higher. Watch the trend as much as the level - a shrinking margin flags rising costs or pricing pressure early.
The standard benchmark is 3:1 - a customer worth three times what they cost to acquire. Between 1:1 and 3:1 is thin once overhead is counted; below 1:1 you lose money on every customer; far above 5:1 usually means you could profitably spend more on growth.
Profit. Multiply lifetime revenue by your gross margin - that is the money actually available to spend on acquiring and serving the customer. Revenue-based LTV overstates what you can afford and is the most common reason LTV:CAC ratios mislead.
Numbers Not Where They Should Be?
These calculators show you the gap. A free growth plan from our consultants shows you how to close it - pricing, costs, acquisition, and retention.