The Rule of 40 for SaaS: Formula, Benchmarks, and Real Examples

If you're evaluating a SaaS company and need one number to quickly separate the high-performers from the struggling ones, the Rule of 40 is arguably the most useful metric in your toolkit. It's fast, it's comparable across companies, and it cuts through the noise of early-stage growth accounting.

But like any benchmark, it's only useful if you understand what it measures, where it breaks down, and how the best companies actually stack up against it.

What Is the Rule of 40 in SaaS?

The Rule of 40 is a heuristic used to evaluate the health of a SaaS business by balancing growth and profitability. The principle is simple: a healthy SaaS company's revenue growth rate plus its profit margin should equal or exceed 40%.

It was popularized around 2015 by venture capitalist Brad Feld and later amplified by Bessemer Venture Partners, among others. The rule emerged as a practical answer to a persistent tension in SaaS investing: early-stage companies often sacrifice profitability to grow fast, making traditional valuation metrics hard to apply. The Rule of 40 gave investors and operators a single composite score to assess whether that trade-off was being made responsibly.

At its core, it acknowledges that SaaS companies exist on a spectrum — some grow explosively but burn cash, others are profitable but growing slowly. The Rule of 40 says both approaches are valid, as long as they add up to 40 or more.

The Rule of 40 Formula

The formula is straightforward:

Rule of 40 Score = Revenue Growth Rate (%) + Profit Margin (%)

For example:

• A company growing at 50% YoY with a -15% profit margin scores 35 — just below the threshold
• A company growing at 25% YoY with a 20% profit margin scores 45 — solidly above it
• A company growing at 60% YoY with a -10% profit margin scores 50 — strong performance

Which Profit Margin to Use?

This is where the formula gets debated. There are three common choices:

1. EBITDA Margin The most common choice in later-stage and public market analysis. EBITDA strips out interest, taxes, depreciation, and amortization, giving a cleaner picture of operating cash generation. It's useful for comparability but can still obscure heavy stock-based compensation.

2. Free Cash Flow (FCF) Margin Increasingly preferred by sophisticated investors. FCF margin captures actual cash generation after capital expenditures and working capital changes, making it harder to game. Bessemer and others have shifted toward FCF margin as the preferred denominator for the Rule of 40.

3. Operating Income Margin (EBIT) Less commonly used, but appropriate if you want a GAAP-consistent view of profitability before financing effects.

For early-stage companies where EBITDA and FCF are deeply negative, the formula still applies — the growth rate simply needs to compensate for the drag. A Series B company burning aggressively might score -20% on profitability but justify it with 70%+ growth.

Which Revenue Metric to Use?

Most practitioners use Annual Recurring Revenue (ARR) growth rather than total revenue growth for pure-play SaaS businesses. For companies with meaningful professional services or one-time revenue, using ARR isolates the recurring engine more accurately.

Why 40? The Logic Behind the Threshold

The 40% threshold wasn't derived from rigorous statistical analysis — it emerged from pattern recognition among successful SaaS businesses. But the math behind it is intuitive.

A mature SaaS business growing at 20% annually is performing well but not spectacularly. To justify a premium valuation, it needs to demonstrate durable unit economics — and a 20% FCF margin alongside that growth rate signals exactly that. Conversely, a company growing at 60% can absorb significant losses because the compounding math on its ARR base is working in its favor.

Research from McKinsey & Company found that software companies scoring above 40 on this rule command valuation multiples roughly twice those of companies below 40, controlling for other factors. Bain & Company's analysis of public SaaS companies showed that Rule of 40 scores were among the strongest predictors of long-term total shareholder return — stronger than growth alone or profitability alone.

The rule also becomes more predictive over time. For companies under $50M ARR, growth tends to dominate the score. As companies scale past $100M ARR, profitability improvement becomes increasingly important to maintain the composite metric.

Rule of 40 Benchmarks by Stage

Understanding context matters. Here's how the Rule of 40 typically looks across company stages:

These are directional benchmarks, not hard rules. The median Rule of 40 score for public SaaS companies has historically hovered around 35–40, meaning the median public SaaS company is at the threshold, not comfortably above it.

During the 2020–2021 SaaS bull market, many companies temporarily blew past these benchmarks on growth alone. The post-2022 correction brought more balance — investors began penalizing growth that came at the cost of deteriorating margins, leading to a broader industry shift toward "efficient growth."

Rule of 40 Companies: Real Examples

Looking at actual public SaaS companies illustrates how the metric plays out in practice.

Companies Scoring Well Above 40

Veeva Systems has historically been a Rule of 40 standout, combining consistent 15–20% growth with EBITDA margins above 30%, producing scores in the 45–55 range. Its vertical SaaS focus in life sciences has allowed for premium pricing and lower churn.

Palantir presents a different profile — more volatile scores depending on the period, but has posted strong Rule of 40 numbers during periods of accelerating government contract growth combined with improving operating leverage.

Datadog during its high-growth phase (2020–2022) posted Rule of 40 scores above 60, driven by 60%+ revenue growth. As growth has moderated to the 25–30% range, profitability improvement has become critical to maintaining its score above 40.

Companies Navigating the Threshold

Salesforce is instructive for large-cap SaaS. As the company matured, revenue growth slowed from 20%+ to the mid-teens. Activist investor pressure in 2022–2023 forced a deliberate shift toward margin expansion. By fiscal year 2024, Salesforce had pushed operating margins above 20% while maintaining ~11% revenue growth — a Rule of 40 score around 31–33, slightly below the threshold but on an improving trajectory.

HubSpot has oscillated around the 40 mark for several years. In periods of aggressive hiring and S&M investment, its Rule of 40 score dips below 40. During periods of more disciplined growth, it comfortably exceeds it. This volatility itself tells a story about the trade-offs management is making in real time.

Companies That Struggled

Zendesk before its 2022 acquisition attempt showed Rule of 40 scores in the 20–30 range — growth had slowed to 20–25% while profitability improvement lagged. The pressure from activist investors reflected, in part, the market's dissatisfaction with a composite score that had drifted meaningfully below 40.

Limitations of the Rule of 40

No single metric is complete, and the Rule of 40 is no exception. Understanding its limitations helps you use it more precisely.

It doesn't capture capital efficiency. A company that raised $500M to post a Rule of 40 score of 42 is telling a very different story than one that reached the same score on $50M raised. Metrics like the Burn Multiple or ARR per dollar raised add essential context.

It can be gamed through cost-cutting. A company that slashes R&D to boost its profit margin might hit 40 while hollowing out its future growth engine. Always look at the components, not just the composite score.

It's backward-looking. The Rule of 40 reflects past performance. For early-stage companies, forward-looking ARR growth rates and net revenue retention (NRR) often matter more.

Margin definitions vary. If you're comparing companies without standardizing on EBITDA vs. FCF vs. operating income, you're not making an apples-to-apples comparison. Always clarify which profit metric is being used.

Industry dynamics affect the threshold. In infrastructure software or security SaaS, higher baseline margins are achievable. In highly competitive horizontals like CRM or marketing automation, the trade-offs are structurally different.

How VCs and LPs Actually Use the Rule of 40

For venture investors, the Rule of 40 is most useful as a portfolio monitoring and benchmarking tool rather than a primary investment criterion at early stages. At Series A, no investor is passing on a company because it scores 25 — the question is whether the trajectory suggests it can hit 40+ at scale.

At growth equity and late-stage investment rounds, the Rule of 40 becomes a central part of diligence. A company heading into a $100M+ financing round at a $1B+ valuation needs to demonstrate a clear path to Rule of 40 performance, even if it's not there yet.

For LPs evaluating VC fund portfolios, aggregate Rule of 40 metrics across a fund's SaaS holdings can signal portfolio quality. A fund whose companies have median Rule of 40 scores in the 50s versus the 30s is managing a meaningfully different risk profile.

Key Takeaways

• The Rule of 40 formula is Revenue Growth Rate (%) + Profit Margin (%) ≥ 40
• Free cash flow margin is increasingly the preferred profit metric for accurate measurement
• The median public SaaS company scores around 35–40, making the threshold a genuine differentiator, not an easy bar
• High-performers like Veeva and Datadog have consistently scored 50+, often by combining strong growth with improving operating leverage
• The rule works best as part of a broader framework — pair it with NRR, CAC payback period, and Burn Multiple for a complete picture
• As SaaS markets mature, the balance between growth and profitability will continue shifting — companies that can sustain scores above 40 while growing at scale represent the true elite of the asset class