The Rule of 40 states that a healthy SaaS company's revenue growth rate plus profit margin should equal or exceed 40%. It balances growth against profitability and gives you a single number to assess overall business health.
The Formula
Rule of 40 Score = Revenue Growth Rate (%) + Profit Margin (%)
A company growing at 50% with a -15% profit margin scores 35 (below 40). A company growing at 25% with a 20% profit margin scores 45 (above 40). Both paths to 40 are valid. The rule says you can burn money if you are growing fast, or grow slowly if you are profitable.
Check the SaaS Benchmarks tool to see how your Rule of 40 score compares to industry medians by stage and vertical.
Why PMs Should Care
Product decisions directly affect both sides of the equation. Building features that drive expansion revenue increases growth rate. Reducing support costs through better UX improves margin. Every prioritization decision shifts the balance.
Understanding your company's Rule of 40 position tells you how to prioritize:
Below 40, growth-limited: Invest in features that drive acquisition and expansion. Activation flows, viral mechanics, and upgrade paths. Score these higher in your RICE analysis.
Below 40, margin-limited: Invest in efficiency. Self-serve onboarding, better docs, and features that reduce support tickets. These improve margin without requiring new revenue.
Above 40: You have room to invest. Experiment with new product lines, enter adjacent markets, or invest in platform capabilities that pay off long-term.
The Tradeoff Curve
Early-stage companies (pre-$10M ARR) should lean heavily toward growth, even at negative margins. The market rewards fast growers with higher valuations per dollar of revenue. A company growing at 80% with -40% margin (Rule of 40 score: 40) is valued higher than one growing at 20% with 20% margin (same score: 40).
After $50M ARR, the curve flips. Investors want a path to profitability. Growth alone stops justifying losses. The balance shifts toward 20-30% growth with 15-25% margins.
Product Strategy Implications
If your company needs to improve its Rule of 40 score, the PM team is the first lever. Use the OKR Generator to set targets that address the weaker side.
Pricing and packaging changes often have the highest impact. A well-designed tier upgrade path can shift NRR from 100% to 115%, adding 15 points to the growth side without acquiring a single new customer. The north star finder can help you identify which product metrics most directly drive your Rule of 40 score.