Business topic

Grow a Business calculators

Price for margin, find the break-even point, and value customers so growth decisions are grounded in unit economics.

Reviewed by BoringToolsKit · August 24, 2026 · Planning information, not professional advice.

What this covers

Grow a Business: the big picture

Growing a business is unit economics: what each sale contributes after costs, how many sales cover the fixed costs, and what a customer is worth over time. Once you know margin, break-even, and customer lifetime value, growth channels — ads, commissions, marketplaces — become math instead of guesses. BoringToolsKit's business tools compute the margin, the break-even units, the lifetime value, and the ad budget that still leaves a profit.

  • Margin is what a sale contributes after variable costs.
  • Break-even is fixed costs divided by contribution per unit.
  • Customer lifetime value tells you what you can afford to spend to acquire one.
  1. Price for the margin you need after costs.
  2. Find how many units cover fixed costs (break-even).
  3. Compare customer lifetime value against acquisition and ad costs.
Worked example

Worked example: a $40 product with $18 cost

  1. Step 1: Profit Margin and Markup Calculator — Enter $40 price and $18 cost See: 55% margin — $22 contribution per sale
  2. Step 2: Break-Even Units Calculator — Enter $12,000 monthly fixed costs with $22 contribution See: 546 units a month to break even
  3. Step 3: Customer Lifetime Value Calculator — 3 orders a year × 4 years at $22 contribution See: About $264 lifetime value — your ceiling for acquisition spend

Numbers depend on the inputs you enter; the walkthrough shows one realistic scenario.

Tools for Grow a Business