Rule of 40
In short
The Rule of 40 is a rule of thumb for software companies: your revenue growth rate plus your profit margin should equal or exceed 40 percent. It tests whether a company balances growth and profitability.
The rule lets a fast-growing company run at a loss and a slower company earn high margins, as long as the two together clear the bar.
How to calculate it
Add the annual revenue growth rate to a profit margin, both in percent. Companies commonly use EBITDA margin or free cash flow margin. Pick one and use it consistently.
Examples
Say a company grows revenue 50 percent with a negative 5 percent margin. Its score is 45, which passes. Another grows 15 percent with a 20 percent margin. Its score is 35, which falls short.
Why GTM teams should care
The rule frames spending trade-offs. If growth slows, margin must rise, and the reverse. Sales and marketing budgets are usually the largest lever, so the score affects hiring, ad spend, and quota plans.
- Growth side: Pipeline generation, win rate, and expansion revenue lift the first number.
- Margin side: Sales efficiency, CAC payback, and churn lift the second number.
Limits of the rule
- A rule of thumb: It is not a law. Stage matters; very early companies are often judged on growth alone.
- Metric choice changes the score: EBITDA, operating, and free cash flow margins give different results.
- Hides the mix: A score of 40 can come from healthy unit economics or from short-term cost cutting. Look at retention and payback too.
How to improve your score
- Reduce churn: Keeping revenue lifts growth without new acquisition cost.
- Improve targeting: Better fit means lower CAC and higher win rates.
- Prune low-return spend: Cut channels that do not pay back within your target window.
Rule of 40 FAQs
What is the Rule of 40?
The Rule of 40 is a guideline for software companies stating that revenue growth rate plus profit margin should total at least 40 percent. It checks whether a business is balancing growth with profitability rather than maximizing only one.
How do you calculate the Rule of 40?
Add your annual revenue growth rate to your profit margin, both as percentages. Many companies use EBITDA margin or free cash flow margin. For example, 30 percent growth plus a 10 percent margin gives a score of 40.
Which profit margin should you use for the Rule of 40?
There is no single standard. Common choices are EBITDA margin and free cash flow margin. What matters is using the same measure over time and stating which one you picked, because different margins can produce noticeably different scores.
Does every SaaS company need to meet the Rule of 40?
No. It is a rule of thumb, not a requirement. Early-stage companies often prioritize growth and may fall short, while mature companies are judged on it more often. Use it alongside retention, payback, and efficiency metrics.
