Product Business Case Calculator
Model a product bet in two minutes. Enter the build cost and a three-year account ramp to see NPV, payback, the break-even level, and what happens in a downside case.
| Year | Accounts | Revenue | Net cash flow |
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How to read the result
Net cash flow each year is revenue times gross margin, less the fixed running cost, less the acquisition cost of the accounts added that year. Year 0 is the build cost. NPV discounts each year's cash flow back to today at your chosen rate, so a positive NPV means the bet returns more than that rate. Payback is the point where cumulative cash turns positive, and it shows how long the money is at risk. Account counts are net of churn.
The number to focus on is the break-even. If NPV stays positive even when you win only a fraction of the plan, the case does not depend on a single favorable assumption. If it needs close to 100 percent of the plan, the risk is concentrated in your ramp and the right first step is a small pilot, not full funding. Change one input at a time to see which assumption moves the answer most, then test that one first.
The full method, with a worked example that matches the defaults here, is in how to build a business case for a product bet. To size the account numbers from the bottom up, use the market sizing calculator and read market sizing for expansion. Check that each account is worth its acquisition cost with the LTV:CAC calculator, and weigh the option against alternatives in build, buy, or partner. The wider frame for choosing which bets deserve a case is in how to write a product strategy.
These are planning estimates, not a forecast. Replace the defaults with numbers you can defend, and show the range.
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Built by Deepanshu Grover, a Senior Product Strategy Consultant and AI builder in Paris. Runs entirely in your browser, nothing is sent anywhere. About · Get in touch