Rule of 40 Calculator
Grow fast or run profitably — early-stage software is told to pick one, but the best companies are scored on the sum of both. Enter your growth rate and your margin, and this tool returns the single number public-market investors use to judge whether a SaaS business is balancing the two well.
The Rule of 40 says a healthy SaaS company’s revenue growth rate plus profit margin should be at least 40. A business growing 50% can afford to burn at a −10% margin and still pass; one growing 15% needs a 25% margin to clear the bar. It is a balance, not a target for either input alone — you trade growth for profit and back as you mature. Margin is usually measured as free-cash-flow or EBITDA margin; pick one and use it consistently.
Rule of 40 Calculator inputs and result
| Score | What it means |
|---|
How to use this calculator
- Pick a growth measureUse year-over-year revenue or ARR growth. Be consistent period to period; switching between MoM-annualized and true YoY will make the score jump for no real reason.
- Pick one margin definitionFree-cash-flow margin and EBITDA margin both appear in Rule of 40 analyses, and they can differ a lot. Choose one, label it, and stick with it so comparisons stay honest.
- Enter both — margin can be negativeHigh-growth companies often run a negative margin. That is fine: a −10% margin still passes if growth is 50%+. Type the minus sign; the tool sums the two.
- Read the score, not the inputsThe whole point is the sum. A passing score can come from many mixes — fast and burning, or slow and profitable. The verdict tells you which lever to work if you fall short.
- Export for the boardCopy a share link, download the CSV, or print a one-pager for the strategy or board discussion.
RGM Expert Says
The Rule of 40 is the metric we use to settle the eternal ‘growth versus profitability’ argument inside a leadership team, because it reframes it as a trade-off rather than a binary. The moment a CEO sees that dropping growth from 40% to 25% only passes if margin climbs fifteen points, the conversation stops being ideological and starts being arithmetic. That clarity is most of the value.
The trap we watch for is definitional sloppiness. Two people in the same room will compute the score with different margins — one using EBITDA, one using free cash flow — and reach opposite conclusions about the same company. We force the team to lock one definition before debating the number, because a Rule of 40 calculated on inconsistent inputs is just a vibe with a decimal point.
We also remind clients that 40 is a threshold for relatively mature companies, not a verdict on a seed-stage startup. A young company burning hard to capture a market can be doing exactly the right thing while failing the Rule of 40 — the metric earns its authority once growth has scaled enough that profitability is a real choice rather than a premature constraint.
How it works
The Rule of 40 is the simplest composite in SaaS: add two percentages that pull in opposite directions and see if the sum clears the line.
- Revenue growth rate — year-over-year revenue or ARR growth, as a percent.
- Profit margin — free-cash-flow or EBITDA margin as a percent; may be negative.
- Score — the sum; 40 or higher is the conventional pass.
Worked example: 30% revenue growth + 12% FCF margin = a score of 42, which clears the 40 threshold. A company growing 55% at a −8% margin scores 47 and also passes. The rule’s origins and nuances are covered in the Rule of 40 deep dive.
Why the Rule of 40 became the SaaS scorecard
The Rule of 40 caught on because it captures the central tension of software economics in one number: growth and profitability compete for the same dollars, and a healthy company balances them rather than maximizing either alone. Investor Brad Feld helped popularize the rule, and Bessemer’s cloud research has shown that public software companies clearing 40 consistently command higher revenue multiples. It is shorthand for ‘efficient growth’ that fits on a single slide.
Its power is that it refuses to crown a single strategy. A company can pass by growing 60% while burning, or by growing 15% at a 25% margin — both are legitimate. That flexibility is why it survives across stages: early companies pass on the growth side, mature ones on the margin side, and the metric naturally tracks the journey from blitzscaling to durable profitability as the growth-margin mix shifts.
The caveat keeps it honest: the Rule of 40 is a screen, not a strategy. It says nothing about which lever to pull, and a company can game it short-term by slashing investment to inflate margin at the cost of future growth. Read it alongside the burn multiple and net revenue retention, which reveal whether the growth behind the score is efficient and durable rather than bought.
How to read the Rule of 40 score
40 is the conventional pass line for relatively mature SaaS. These bands are rules of thumb drawn from public-market analysis, not absolutes — early-stage companies are judged more on the growth input.
| Score | Read | Implication |
|---|---|---|
| Below 20 | Inefficient | Neither fast nor profitable — fix economics |
| 20 to 40 | Below bar | Improving; one lever needs work |
| 40 to 60 | Passing | Healthy growth-profit balance |
| Above 60 | Elite | Rare; commands premium multiples |
What investors say about the Rule of 40
For a healthy SaaS company, your growth rate plus your profit margin should exceed 40%; it is a quick way to see whether you are balancing growth and profitability sensibly.
Efficient growth, not growth at any cost, is what separates the SaaS companies that earn durable premium valuations from those that do not.