how do you calculate the rule of 40

You add the company’s year-on-year revenue growth rate to its profit margin, both expressed as percentages, and check whether the sum is at least 40. For instance, a company growing revenue 30% with a 15% margin scores 45 and clears the bar, while one growing 50% but running a −15% margin scores 35 and falls short. The margin used should be consistent — commonly an EBITDA margin or a free-cash-flow margin rather than net margin — and applied the same way whenever you compare companies.

why does the rule of 40 matter for growth companies

It matters because growth companies constantly trade profitability for expansion, and the Rule of 40 gives a disciplined way to judge whether that trade is being made well. A business burning cash is acceptable if it is buying rapid, durable growth; unacceptable if the growth is slow. By summing the two, the rule stops investors from over-rewarding growth that comes at any cost, or over-penalising a profitable company that has simply matured. It is especially useful for new-age and software businesses whose earnings-based valuations look meaningless in their early years.

what are the limitations of the rule of 40

The Rule of 40 is a rule of thumb, not a valuation, and it has real blind spots. It treats a point of growth and a point of margin as equivalent, when durable growth is usually worth far more than a fleeting margin; it can be gamed by cutting investment to boost short-term margin at the expense of the future; and it says nothing about growth quality, competitive advantage or how long either can last. It also fits fast-growing, often software businesses and is largely meaningless for mature, slow-growth or cyclical companies. Use it as a screen, not a verdict.

What is the Rule of 40 and how to use it

How do you judge a company that is growing fast but losing money, against one growing slowly but highly profitable? The Rule of 40 answers with a single line: revenue growth plus profit margin should clear 40%. Born in the software world, it captures the central trade-off of every growth business — and, used carelessly, it flatters exactly the wrong companies.

One number for a two-way trade-off

A growth company can spend its profits to grow faster, or grow slower and bank the profits. The Rule of 40 says the sum of the two — growth rate + profit margin — should be at least 40%. A company growing 35% at a 5% margin (40) passes; so does one growing 10% at a 30% margin (40). One growing 20% at a −5% margin (15) fails — it is neither expanding fast enough nor profitable enough to justify the mix.

Loading interactive demo…

Set a revenue growth rate and a profit margin and see whether the company clears 40 — then watch how a company can pass on pure growth, pure profitability, or a balance of both.

Worked example

Three companies, one bar

The 40% test

Hyper-growthScore 45 — passes55% growth, −10% margin

BalancedScore 45 — passes25% growth, 20% margin

Mature profitableScore 40 — just passes8% growth, 32% margin

StrugglingScore 23 — fails18% growth, 5% margin

Three very different companies clear the bar in three different ways — pure growth, a balance, or pure profitability — while the fourth, mediocre on both, fails. That is the rule’s appeal: it lets a business earn its keep through growth or profit or a mix, but insists the combination be strong. The failing company is the warning it is designed to catch.

Check yourself

Company A grows revenue 45% with a −8% margin; Company B grows 12% with a 33% margin. How does the Rule of 40 judge them?

Simple bhasha mein

Growth aur profit, ek line mein

Growth company ke liye ek jhat-pat test: revenue growth % + profit margin % ≥ 40. 30% growth + 15% margin = 45, pass. Tezi se badho toh kam profit chalega; jyada profit ho toh dheemi growth chalegi — par dono ka jod 40 paar hona chahiye. Trick se bacho: koi investment kaat ke short-term margin badha ke score phula sakta hai — woh pass fail se bura hai. Software/new-age company pe chalta hai, mature FMCG pe nahi.

What to remember

The Rule of 40 says revenue growth plus profit margin should be at least 40%.
It lets a company earn its keep through growth, profitability, or a balance of both.
It captures a real trade-off single metrics miss — but treats a point of growth and margin as equal.
It can be gamed by cutting investment to lift short-term margin, so judge growth quality too.
It fits fast-growing, software and new-age businesses, not mature or cyclical ones.

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Common questions

Short, direct answers to what people ask about this topic.

what is the rule of 40: The Rule of 40 is a benchmark for growth companies which says that a company’s revenue growth rate plus its profit margin should add up to at least 40%. It emerged from the software and SaaS world as a quick way to judge whether a business is balancing growth and profitability sensibly. The logic is that a company can justify low or negative profits if it is growing fast, or slow growth if it is highly profitable — but the combination of the two should clear the 40% bar. It captures, in one line, the trade-off every growth company faces.
how do you calculate the rule of 40: You add the company’s year-on-year revenue growth rate to its profit margin, both expressed as percentages, and check whether the sum is at least 40. For instance, a company growing revenue 30% with a 15% margin scores 45 and clears the bar, while one growing 50% but running a −15% margin scores 35 and falls short. The margin used should be consistent — commonly an EBITDA margin or a free-cash-flow margin rather than net margin — and applied the same way whenever you compare companies.
why does the rule of 40 matter for growth companies: It matters because growth companies constantly trade profitability for expansion, and the Rule of 40 gives a disciplined way to judge whether that trade is being made well. A business burning cash is acceptable if it is buying rapid, durable growth; unacceptable if the growth is slow. By summing the two, the rule stops investors from over-rewarding growth that comes at any cost, or over-penalising a profitable company that has simply matured. It is especially useful for new-age and software businesses whose earnings-based valuations look meaningless in their early years.
what are the limitations of the rule of 40: The Rule of 40 is a rule of thumb, not a valuation, and it has real blind spots. It treats a point of growth and a point of margin as equivalent, when durable growth is usually worth far more than a fleeting margin; it can be gamed by cutting investment to boost short-term margin at the expense of the future; and it says nothing about growth quality, competitive advantage or how long either can last. It also fits fast-growing, often software businesses and is largely meaningless for mature, slow-growth or cyclical companies. Use it as a screen, not a verdict.

The Rule of 40: growth and profit, on one line

One number for a two-way trade-off

Common questions