SaaS Rule of 40 Calculator (Bessemer & Scale Venture Partners)
Determine if your software company achieves elite growth and profitability balance. The Rule of 40 states that your YoY revenue growth rate plus your Free Cash Flow (FCF) margin should equal or exceed 40%.
Performance Metrics
Annual recurring revenue growth percentage over the trailing 12 months.
Operational free cash flow margin (FCF / Revenue) or EBITDA percentage.
Elite SaaS tier. High valuation multiples and strong investor interest.
According to Bessemer Venture Partners (BVP), public cloud companies exceeding the Rule of 40 command 2.5x higher enterprise valuation revenue multiples compared to those under 40%.
What Is the Rule of 40?
The Rule of 40 is a SaaS performance framework holding that a healthy software company's revenue growth rate plus its profit margin should sum to at least 40. A Rule of 40 calculator adds year-over-year revenue growth percentage to free cash flow margin percentage: a company growing 30% with 15% FCF margin scores 45 and passes; one growing 60% while burning at −30% margin scores 30 and fails. Popularized by Bessemer Venture Partners and refined by Scale Venture Partners, the rule encodes the central tradeoff of SaaS economics — growth and profitability are substitutes, and excellence means getting enough of their sum, not maximizing either alone.
The framework's endurance comes from its balance. Pure growth metrics reward capital destruction; pure profitability metrics punish young companies for investing. The Rule of 40 lets a hypergrowth startup offset negative margins with speed, and lets a slower grower compensate with efficiency — while exposing companies that are both slow-growing *and* unprofitable, the true danger zone. In 2026, after several years of efficiency-first markets, it has evolved from a venture heuristic into a board-level operating standard: public SaaS multiples now correlate more tightly with Rule of 40 scores than with growth alone, which is why CFOs track it quarterly and tie executive comp to it.
Rule of 40 Formula
Variable definitions:
- YoY Revenue Growth Rate % — (Current period revenue − same period last year) ÷ same period last year × 100. Use GAAP revenue (or ARR for private companies, consistently). The standard is year-over-year to neutralize seasonality.
- Free Cash Flow Margin % — (Operating cash flow − capital expenditures) ÷ revenue × 100. FCF is preferred over EBITDA because it reflects actual cash generation after the capex SaaS companies do incur. Some practitioners substitute EBITDA margin or even GAAP operating margin — pick one definition and hold it constant, because the variants can differ by 10+ points.
Passing score: ≥ 40. A score of 40+ indicates a healthy balance; 50+ is strong; 60+ is elite and rare outside the largest platforms.
Common variants: Bessemer's original formulation used growth + FCF margin. Some investors use growth + EBITDA margin (flattering, since it adds back stock comp). The "Rule of 40" name is sometimes stretched to "Rule of 50" or "Rule of 60" for top-quartile framing — the math is identical, only the bar moves.
Worked Example
Take a public-scale SaaS company reporting full-year 2026:
- 2025 revenue: $400M; 2026 revenue: $520M
- YoY growth = ($520M − $400M) ÷ $400M = 30%
- Operating cash flow: $104M; capex: $12M → FCF = $92M
- FCF margin = $92M ÷ $520M = 17.7%
Rule of 40 score = 30 + 17.7 = 47.7 — passes comfortably, with a balanced profile: real growth plus real cash generation.
Contrast two companies that both "pass" differently:
- HypergrowthCo: 75% growth, −20% FCF margin → 55. Passes on velocity. The bet: growth compounds into future margins. Works only if unit economics (NRR, gross margin) are strong underneath.
- EfficientCo: 15% growth, +30% FCF margin → 45. Passes on discipline. The market rewards this profile more generously in downturns — it doesn't need external capital.
And the failure mode: StuckCo at 18% growth and 5% FCF margin → 23. Too slow to be a growth story, too undisciplined to be a cash cow. This is the profile the Rule of 40 is designed to surface, and in 2026 it trades at the steepest discount in SaaS.
Benchmarks
| Score | Rating | Typical profile |
|---|---|---|
| 60+ | Elite | Top-decile public SaaS; commands premium multiples |
| 50–60 | Strong | Best-in-class balance of growth and efficiency |
| 40–50 | Healthy | The passing band; fundable, acquirable, durable |
| 30–40 | Watch | One leg is weak; needs a credible path to 40+ |
| < 30 | Troubled | Neither growing fast nor profitable — demands restructuring |
How the market reads it in 2026:
- Public SaaS multiples track Rule of 40 scores more closely than growth alone. A 45 at balanced 25/20 often trades richer than a 45 built as 70/−25, because the market discounts cash-burning growth.
- Private fundraising uses 40 as a screening threshold for growth rounds; below it, expect valuation haircuts or structure.
- Stage adjustments: early-stage (Series A/B) companies are rarely held to 40 — investors accept sub-40 for genuine hypergrowth. The bar hardens from Series C onward.
Frequently Asked Questions
What is the Rule of 40 in SaaS?
The Rule of 40 states that a SaaS company's year-over-year revenue growth rate plus its free cash flow margin should total at least 40. It balances growth against profitability: fast growers can offset negative margins, and slower growers can compensate with high margins. Scores above 40 indicate healthy unit economics; above 50 is strong.
How do you calculate the Rule of 40?
Add two percentages: (1) YoY revenue growth rate = (current revenue − prior-year revenue) ÷ prior-year revenue × 100; (2) free cash flow margin = (operating cash flow − capex) ÷ revenue × 100. The sum is the score. Use consistent definitions period to period — mixing FCF margin one quarter with EBITDA margin the next makes the trend meaningless.
What is a good Rule of 40 score?
40 is the passing line. 40–50 is healthy, 50–60 is strong, and 60+ is elite. Below 30 signals real trouble — the company is neither growing fast enough nor profitable enough. Context matters: early-stage startups are judged more leniently, while public companies live and die by the number.
Should I use FCF margin or EBITDA margin?
Free cash flow margin is the standard and the more honest measure — it captures actual cash generation. EBITDA margin flatters the score by adding back stock-based compensation, which is a real (if non-cash) cost of talent. Bessemer's canonical formulation uses FCF. If you use EBITDA, say so explicitly; sophisticated readers will mentally haircut the number otherwise.
Does the Rule of 40 apply to early-stage startups?
Loosely. Pre-Series C companies are generally expected to prioritize growth, and investors tolerate sub-40 scores for genuine hypergrowth (100%+ YoY). But the framework still disciplines: a seed company at 40% growth and −60% margins (score −20) is burning without velocity, and no stage excuses that. Use it as a guardrail early, a target from Series C on.
Why 40 and not 30 or 50?
Forty emerged empirically from Bessemer's analysis of public SaaS companies — it was roughly the line separating durable compounders from the rest. It's a heuristic, not a law of physics. Some investors use 50 for top-quartile framing. The value isn't the number itself but the discipline of holding growth and profitability in one equation instead of optimizing either in isolation.