Revenue

Magic Number Calculator

Magic Number measures how much new annualized revenue a SaaS company generates for every dollar of sales and marketing spent the prior quarter, a fast read on whether it's time to invest more in growth or fix efficiency first.

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Magic Number

1.50

What This Means

Above 0.75 is generally considered efficient enough to justify increasing sales and marketing spend; below 0.5 signals an efficiency problem to fix first.

The Formula

Magic Number = (Current Quarter ARR - Prior Quarter ARR) × 4 / Prior Quarter Sales and Marketing Spend

Why It Matters

A rule-of-thumb widely used by SaaS investors: above 0.75, a company is generally considered efficient enough to justify accelerating sales and marketing spend; below 0.5, spend is often outpacing what it's producing, and the more urgent priority is fixing efficiency before adding fuel.

Example

A company's ARR grows from $2,000,000 to $2,300,000 in a quarter, after spending $800,000 on sales and marketing the prior quarter. Magic Number is ($300,000 times 4) divided by $800,000, which equals 1.5, comfortably above the 0.75 threshold typically read as efficient.

Frequently Asked Questions

  • Above 0.75 is commonly cited as efficient enough to justify increasing sales and marketing investment; below 0.5 usually signals an efficiency problem worth fixing before spending more.

  • It annualizes one quarter's ARR growth so it can be compared directly against the prior quarter's spend, which is already a full-quarter figure.