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Rule of 40 calculator

Add your growth rate and profit margin to see if your SaaS clears the 40 threshold — and whether you're leaning on growth or profitability.

%

Year-over-year recurring revenue growth.

%

EBITDA, FCF, or operating margin. Can be negative.

Rule of 40 Score
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Status
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Profile
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Margin vs Target
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Growth Contribution
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Margin Contribution
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Growth Share of Score
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Smart insights

Combinations that hit 40

Every row scores exactly 40 — the margin needed at each growth rate to pass.

Growth Rate Margin to Reach 40 Profile

Score bands

Below 40
Fails

growth & margin out of balance

40 to 60
Healthy

solid balance for scale

Above 60
Elite

top-decile SaaS

What is the Rule of 40?

The Rule of 40 is a benchmark for balancing growth and profitability in SaaS. It says your year-over-year revenue growth rate plus your profit margin should be at least 40%. High growth justifies thin or negative margins; slower growth demands profit.

It's a heuristic, not a hard law. Its value is as a single number that lets you compare companies at very different stages, and as a trend that flags when growth and profitability fall out of balance.

The formula

Score = Growth Rate % + Profit Margin %

Example: 35% growth and a 10% margin:

35 + 10 = 45 (Pass)
A negative margin still counts: 55% growth − 15% margin = 40.

Growth-led vs profit-led

Growth

Burning to grow

If most of your score comes from growth and your margin is thin or negative, you're betting that growth compounds before the cash runs out. That's fine at scale with strong retention, risky if growth decelerates.

Profit

Efficient and durable

If your score leans on margin, you're durable and self-funding but may be leaving growth on the table. Investors will ask whether you could reinvest profit to accelerate without breaking the score.

FAQ

Frequently asked questions

What is the Rule of 40?

The Rule of 40 is a SaaS health benchmark that says your year-over-year revenue growth rate plus your profit margin should add up to at least 40%. It captures the trade-off between growth and profitability: a company growing fast can afford to burn cash, while a slower-growing company should be profitable. Adding the two gives a single score to compare companies at different stages.

How do you calculate the Rule of 40?

Add your YoY revenue growth rate to your profit margin. If you grow 30% and run a 15% margin, your score is 45 — you pass. The margin can be negative: 50% growth at a −15% margin still scores 35, which fails. Use a consistent margin definition (EBITDA, free cash flow, or operating margin) and the same revenue growth basis.

Which profit margin should I use?

There's no single rule, but consistency matters. EBITDA margin and free cash flow (FCF) margin are the most common choices for the Rule of 40 because they approximate cash generation. Operating margin works too. Whatever you pick, use it consistently over time and when comparing against peers, since the score shifts depending on which margin you plug in.

Is the Rule of 40 a hard cutoff?

No. It's a rough heuristic, not a law. A score of 38 isn't a failure and 42 isn't a guarantee of health. It's most useful as a trend and a sanity check: are you balancing growth and profitability, or leaning so hard on one that the other collapses? Two companies can both score 40 with very different risk profiles.

Does the Rule of 40 apply to early-stage startups?

Less so. Early-stage companies often grow 100%+ while burning heavily, so they clear 40 on growth alone, and the margin term tells you little. The Rule of 40 becomes most meaningful at scale — roughly $10M+ ARR — when growth naturally decelerates and the market starts expecting a path to profitability.

Can you pass the Rule of 40 while losing money?

Yes, if growth is high enough. A company growing 60% with a −15% margin scores 45 and passes. That's the point of the rule: rapid growth justifies burning cash, because each point of growth compounds future revenue. The risk is that growth slows before margins improve, which is why the score should be watched as a trend, not a one-time check.

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