Rule of 40
A SaaS benchmark stating that growth rate plus profit margin should together equal or exceed 40%.
The Rule of 40 is a rough heuristic for evaluating whether a SaaS company's balance of growth and profitability is healthy: add the year-over-year revenue growth rate to the profit margin (often EBITDA margin or free cash flow margin), and the sum should be roughly 40% or higher. A fast-growing but deeply unprofitable company and a slow-growing but highly profitable one can both satisfy the rule.
It's most useful as a directional benchmark for growth-stage and later companies, particularly public or pre-IPO SaaS businesses being compared on trading multiples — it's less meaningful for very early-stage startups still finding product-market fit, where growth rate volatility makes the math noisy.
Rule of 40 score = year-over-year revenue growth rate (%) + profit margin (%)A company is growing revenue 55% year-over-year but running an EBITDA margin of negative 10%. Rule of 40 score = 55 - 10 = 45, above the 40 threshold despite being unprofitable, because growth is strong enough to compensate.
Use the Rule of 40 as a sanity check on the growth-versus-burn tradeoff when setting an annual plan, not as a rigid target — a company well below 40 with clearly improving trends can still be a healthy business, while one drifting further below it over time is a real warning sign.
Does the Rule of 40 apply to early-stage startups?
It's less useful pre-Series-A or pre-product-market-fit, since growth rates are volatile and small revenue bases make the math swing wildly — it's more meaningful for growth-stage and public SaaS companies.
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