Magic Number Calculator: SaaS Efficiency Ratio
Measure how efficiently your sales and marketing spend generates new annual recurring revenue.
The SaaS Magic Number measures sales efficiency: New ARR ÷ Prior Period Sales & Marketing Spend. Above 1.0 generally means you can invest more in GTM efficiently.
Annual recurring revenue from new customers this quarter
Total S&M spend from the previous quarter
Magic Number
0.83
Good, efficient growth, room to optimize further.
Moderate efficiency. The engine works but needs optimization. Focus on improving conversion rates and reducing CAC before scaling spend.
How it works
The Magic Number tells you how many dollars of new ARR you generate for every dollar spent on sales and marketing. A number above 1.0 means efficient growth; below 0.5 signals inefficiency.
How to use this calculator
Follow these steps to get an accurate Magic Number result.
- Open the Magic Number Calculator.
- Enter New Bookings (ARR): the total annual recurring revenue from new customers won this quarter.
- Enter Sales & Marketing Spend: total S&M spend from the previous quarter (accounts for the lag between spend and revenue).
- Review your Magic Number ratio. Above 1.0 means efficient GTM spend; below 0.5 signals a need to rethink your go-to-market strategy. Use it alongside the Burn Multiple and Rule of 40 calculators for a full efficiency picture.
Worked examples
Plug in sample numbers to see how the Magic Number formula works in practice.
Quarterly Magic Number
- New ARR this quarter
- $300,000
- Prior quarter S&M spend
- $250,000
Magic Number = $300,000 ÷ $250,000 = 1.2
Benchmarks
Directional ranges—always prefer your own baselines and unit economics.
| Context | Guidance |
|---|---|
| Under 0.5 | Inefficient — fix GTM before scaling spend |
| 0.5–0.75 | Fair — improve efficiency |
| 0.75–1.0 | Good |
| Above 1.0 | Strong — room to invest more in growth |
Common mistakes
- Using same-period S&M spend — Use prior-period S&M to account for sales cycle lag.
- Including expansion incorrectly — Be consistent: most definitions use net new ARR from new business (check your board standard).
Frequently Asked Questions
What is the SaaS Magic Number?
The Magic Number is a SaaS efficiency metric that divides new ARR (annual recurring revenue from new customers) in a given quarter by the sales and marketing spend from the previous quarter. It measures how efficiently your GTM engine converts spend into recurring revenue.
How do you calculate the Magic Number?
Magic Number = New Bookings (ARR this quarter) ÷ Sales & Marketing Spend (previous quarter). Example: $600K in new ARR on $500K S&M spend = 1.2 Magic Number. The previous-quarter spend accounts for the lag between investment and revenue generation.
What is a good Magic Number for SaaS?
Above 1.0 is excellent (you generate more ARR than you spend). 0.75–1.0 is good. 0.5–0.75 is fair. Below 0.5 needs attention. Early-stage companies with high growth may accept lower numbers, but efficient companies consistently achieve 0.75+. Top-quartile public SaaS companies average around 1.0–1.5.
How is the Magic Number different from CAC payback?
The Magic Number measures top-line GTM efficiency: how much new ARR your S&M spend produces. CAC payback measures per-customer profitability: how many months to recover acquisition cost. The Magic Number looks at aggregate portfolio efficiency; payback looks at individual unit economics. Both are important but answer different questions.
When should I use the Magic Number vs. CAC?
Use the Magic Number for GTM efficiency and when deciding how much to invest in sales and marketing. Use CAC for per-customer unit economics and pricing decisions. The Magic Number answers "should I spend more on growth?" while CAC answers "is each customer profitable?"
Can the Magic Number be negative?
If you have negative net new ARR (churn exceeds new bookings), the formula does not produce a meaningful result. The Magic Number is designed for companies with positive growth. For companies with negative growth, focus on reducing churn before measuring GTM efficiency.
Related Calculators
Burn Multiple
Calculate your SaaS Burn Multiple with the standard formula (Net Burn ÷ Net New ARR) to measure capital efficiency.
Burn Multiple = Net Burn ÷ Net New ARR
Rule of 40
Combine revenue growth rate and EBITDA margin to measure overall SaaS business health.
Rule of 40 = Revenue Growth % + EBITDA Margin %
MRR Calculator
Calculate monthly recurring revenue (MRR) instantly: Active Customers × ARPU, with growth and churn context for SaaS.
MRR = Active Customers × ARPU
ARR Calculator
Calculate annual recurring revenue (ARR) instantly: MRR × 12, the investor-standard SaaS scale metric.
ARR = MRR × 12