Rule of 40 calculator (SaaS growth + profitability)

Rule of 40 Calculator — SaaS Growth + Profitability Score

The Rule of 40 is the benchmark SaaS investors use to evaluate whether a company has found the right balance between growth and profitability. It collapses two competing priorities into one number: add your ARR growth rate and EBITDA margin. Score 40 or above, and you're in the healthy zone. Below 40, and investors start asking hard questions.

The Formula

Rule of 40 Score = ARR Growth Rate (%) + EBITDA Margin (%)

ARR Growth Rate = (Current ARR − Prior Year ARR) / Prior Year ARR × 100. EBITDA Margin = EBITDA / Current ARR × 100 (EBITDA can be negative for high-growth companies). Scores are additive — a 60% growth / -20% margin company scores 40, same as a 20% growth / 20% margin company.

Score Benchmarks

≥60: Elite — top-tier growth efficiency. Investor darling territory.
40–59: Healthy — strong balance of growth and efficiency.
20–39: Fair — may need to improve growth, margins, or both.
<20: Concerning — growth slowdown with inadequate margin structure.

ARR Stage Benchmarks

Early-stage companies (<$1M ARR) routinely score 60–120+ because percentage growth rates are high. As ARR scales, growth rates compress naturally. A $50M ARR company growing 50% is considered exceptional; the same percentage growth at $1M ARR is simply expected. Benchmark your score against peers at similar ARR levels, not across all stages.

Gross Margin and Rule of 40

Gross margin matters underneath the Rule of 40. A company with 60% gross margin scoring 40 on Rule of 40 is in worse shape than one with 80% gross margin at the same score — because underlying unit economics are weaker. Best-in-class SaaS has 70–85% gross margins. If your gross margin is below 60%, focus on pricing and COGS reduction before celebrating a 40+ score.

Improving Your Score

Growth levers: increase new ARR through better sales execution, expand existing customers (NRR >110%), reduce churn. Margin levers: shift customer success to scale with headcount, reduce infrastructure costs, automate repetitive processes, improve gross retention. The fastest score improvements usually come from reducing CAC payback while maintaining growth, or from operational efficiency gains as ARR scales into fixed cost leverage.