Rule of 40
A SaaS health benchmark stating that revenue growth rate plus profit margin should exceed 40%.
Definition
The Rule of 40 is a heuristic for evaluating the health of a software business: a company's annual recurring-revenue growth rate plus its profit margin (commonly EBITDA or free-cash-flow margin) should sum to at least 40%. Popularized among SaaS investors (often attributed to Brad Feld), it captures the core trade-off between growth and profitability — a company can grow fast and burn cash, or grow modestly while highly profitable, but the combination should clear the 40% bar. It is most reliable for scaled, mature SaaS businesses rather than early-stage startups.
Examples
Growth 30% + EBITDA margin 15% = 45 → passes the Rule of 40
Growth 60% + margin −15% = 45 → passes despite burning cash, because growth is high
Growth 20% + margin 10% = 30 → fails; the company needs more growth or more profit
Calculation
How to Calculate
Add the year-over-year recurring revenue growth rate to the profit margin (EBITDA or free-cash-flow margin). If the sum is 40 or higher, the company is considered healthily balanced between growth and profitability. A high-growth company can carry negative margin and still pass; a slow-grower must be highly profitable to clear the bar.
Formula
Rule of 40 = Revenue Growth Rate (%) + Profit Margin (%) ≥ 40%Unit of Measurement
%
Operation Type
add
Formula Variables
Industry Benchmarks for Rule of 40
Typical performance ranges by industry segment. Benchmarks vary by platform, audience maturity, and attribution window — treat these as starting points, not targets.
Public SaaS (median)
- Typical range
- ≈34% (LTM)
- Median
- 34%
More than half of public SaaS companies do not currently clear the Rule of 40.
Passing threshold
- Typical range
- ≥40%
- Median
- 40%
40+ is considered healthy across company sizes; top performers reach 50–60%+. Some investors instead use a 'Rule of X' that weights growth ~2–3x free-cash-flow margin (Bessemer).
Sources: Meritech Capital benchmarks, Aug 2024, Brad Feld / widely adopted SaaS investor heuristic
Comparison
Related Metrics
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Marketing Efficiency Ratio (MER)
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Annual Recurring Revenue (ARR)
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Monthly Recurring Revenue (MRR)
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Net Revenue Retention (NRR)
Net Revenue Retention (NRR), also called Net Dollar Retention (NDR), measures how much recurring revenue a business retains and grows from its existing customer base over a period — including expansion (upsell, cross-sell, price increases) and net of contraction and churn — while excluding revenue from net-new customers. An NRR above 100% means the existing base grows on its own even before any new sales, which is why it is widely regarded as the single most important growth and durability metric for modern SaaS.
How AdSights helps you track Rule of 40
The Rule of 40 forces a choice between growth and efficiency — and acquisition is where both are won or lost. By revealing which creatives and audiences acquire customers most efficiently, AdSights helps teams protect the margin side of the equation without throttling growth. Cutting waste from underperforming ad variants improves profitability; concentrating spend on proven, scalable creative sustains growth — moving both terms of the Rule of 40 in the right direction at once.
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Common questions about Rule of 40, answered.
