Startup Metrics Advanced

Magic Number

Measures sales efficiency: net new ARR divided by sales and marketing spend in the prior period.

Definition

The magic number is a sales efficiency metric calculated as net new ARR in a quarter divided by the prior quarter's sales and marketing spend. A magic number above 0.75 suggests efficient growth and justifies increasing sales spend. Below 0.5 suggests the go-to-market engine is inefficient. It helps determine whether a company should invest more in sales and marketing or focus on improving unit economics first.

Why it matters

A high magic number means the company can grow efficiently, which extends runway and reduces dilution. A low magic number may lead to cost cuts, especially in sales, which can signal trouble.

Example

A company spent $2M on sales and marketing last quarter and added $1.8M in net new ARR this quarter. Magic number = $1.8M / $2M = 0.9. This indicates strong sales efficiency and the company should continue scaling sales spend.

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This definition is an educational summary. It is not legal, tax, or investment advice. Specific terms in your equity grant or company documents may differ.