What is Rule of 40?
A balance test for software companies - growth rate plus profit margin should clear 40%.
Rule of 40: definition
Fast growth can justify low or negative margins, and high margins can justify slower growth - but a healthy business should not fail on both. The Rule of 40 captures this trade-off in one number: add the year-over-year revenue growth rate to the profit margin (often EBITDA or free-cash-flow margin), and a result of 40% or more signals a healthy balance. It is a heuristic, not a law, but a widely used one for benchmarking.
The Rule of 40
Revenue Growth Rate (%) + Profit Margin (%) ≥ 40%
A 60% grower losing 15% margin scores 45% (passes). A 10% grower at 25% margin scores 35% (fails). The margin measure (EBITDA or FCF) should be stated.
How Fintra handles it
Fintra tracks revenue growth and margin from the same live financials, so the Rule of 40 is computed from actuals rather than estimates, with the chosen margin measure clearly stated. Planning shows the trade-off directly - how dialing spend up for growth or down for margin moves the combined score - so growth and profitability decisions are made with the balance in view.
- Growth rate and margin drawn from the live ledger
- Rule of 40 score computed with a stated margin measure
- Scenarios show the growth-versus-margin trade-off on the score
Worked example
Frequently asked questions
How do you calculate the Rule of 40?
Add the revenue growth rate (year over year, as a percentage) to the profit margin (as a percentage) for the same period. If the sum is 40% or more, the business passes. State which margin you use - EBITDA and free-cash-flow margin are common - since it changes the result.
What margin should you use for the Rule of 40?
There is no single standard - EBITDA margin, operating margin, and free-cash-flow margin are all used. The choice affects the score, so be consistent and transparent about which margin you apply when comparing companies or periods.
Does the Rule of 40 apply to early-stage startups?
It is most meaningful for companies with enough scale and stable growth to interpret the trade-off - typically past the earliest stages. Very early startups often grow explosively with deep losses, which can distort the score. It is a benchmark, not a hard rule.
Why balance growth and profitability?
Because pursuing either alone can be unhealthy - reckless growth burns cash while over-optimizing margin can starve the business of future revenue. The Rule of 40 rewards combinations of growth and profit that add up to a sustainable trajectory.
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