Metrics & Performance
Rule of 40
Last updated
Quick Answer
A SaaS health metric: a company's revenue growth rate plus profit margin should equal or exceed 40%, balancing growth and profitability.
The Rule of 40 is a heuristic used to evaluate the overall health of a SaaS business by combining growth and profitability into a single number. The formula: Revenue Growth Rate (%) + Profit Margin (%) ≥ 40. A company growing 60% annually with a -20% profit margin scores 40. A company growing 20% with a 20% margin also scores 40.
The metric acknowledges the fundamental tradeoff in SaaS: high-growth companies typically burn cash to acquire customers and build product, while slower-growing companies can afford to focus on profitability. The Rule of 40 says either approach is acceptable — what matters is the combined score.
Profit margin in this context is typically measured as EBITDA margin or free cash flow margin, not GAAP net income. Some investors use revenue growth + operating cash flow margin. Scores above 40 are considered healthy; scores above 60 are exceptional.
In Practice
Snowflake grew 69% year-over-year with a -22% free cash flow margin, for a Rule of 40 score of 47 — healthy. A mature SaaS company growing 15% with a 30% free cash flow margin scores 45 — also healthy, just via a different mix of growth and profitability.
Why It Matters
The Rule of 40 became the dominant SaaS benchmarking metric because it lets investors compare high-growth money-losers to profitable slower-growers on equal footing. Post-2022, as capital became more expensive, investors began weighting profitability more heavily — a 40% growth + 0% margin is viewed less favorably than it was in 2021.
Related Concepts
Further Reading
How to Calculate the Rule of 40: SaaS Health Score Formula
The Rule of 40 combines revenue growth and profit margin to score a SaaS company's overall health. Learn the formula, the benchmarks, and what it really tells investors.
ARR: What Annual Recurring Revenue Means in Venture Capital
ARR (Annual Recurring Revenue) is the single most-watched metric in SaaS venture capital. Here's exactly what it means, how it's calculated, what benchmarks matter, and why VCs obsess over it.
Product-Market Fit: What It Really Means and How to Find It
Product-market fit is the single most important milestone for any startup. This complete guide breaks down what PMF actually means, how to measure it, how VCs evaluate it, and what to do once you've found it — with real examples from Slack, Dropbox, Superhuman, and Notion.
Follow-On Reserve Strategy: How Much to Set Aside and When to Deploy
Learn how to size and deploy follow-on reserves in VC — with benchmarks by fund stage, reserve modeling frameworks, and LP reporting best practices.
When and How to Mark Up Portfolio Companies
Learn when and how to mark up portfolio companies in a VC fund — covering ASC 820 standards, key triggers, sizing methodology, and what LPs expect from your valuation policy.
Investment Committee Best Practices for Small VC Funds
A structured investment committee process is critical for small VC funds. Learn IC best practices, a practical IC memo template, and how to run disciplined investment decisions.
Comparisons
Frequently Asked Questions
What is Rule of 40 in venture capital?
The Rule of 40 is a heuristic used to evaluate the overall health of a SaaS business by combining growth and profitability into a single number. The formula: Revenue Growth Rate (%) + Profit Margin (%) ≥ 40. A company growing 60% annually with a -20% profit margin scores 40.
Why is Rule of 40 important for startups?
Understanding Rule of 40 is critical for founders navigating the fundraising process. It directly impacts deal terms, valuation, and the relationship between founders and investors.
What category does Rule of 40 fall under in VC?
Rule of 40 falls under the metrics category in venture capital. This area covers concepts related to the quantitative measures used to evaluate fund and company performance.
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