What is SaaS magic number? Definition, Formula & Benchmarks

What is saas magic number?

The SaaS magic number measures how efficiently sales and marketing spend converts into new recurring revenue. It divides annualized net-new ARR in a quarter by the prior quarter's S&M spend. Above 0.75 means acquisition is efficient enough to justify pouring in more; below 0.5 means fix the funnel first.

Formula

Magic Number = (Net New ARR in Quarter × 4) ÷ Prior Quarter S&M Spend

Net New ARRQuarter-over-quarter increase in ARR, annualized ×4
Prior Quarter S&M SpendSales and marketing cost in the preceding quarter

Worked example

ARR grows $250K in Q2 (×4 = $1M annualized) and you spent $900K on sales and marketing in Q1. Magic number = $1M ÷ $900K = 1.11, efficient enough to justify stepping on the gas.

Benchmarks by stage

Above 0.75 is considered efficient; recent medians run ~0.8 at $1–5M ARR and ~0.89 at $5–20M ARR.

< 0.5 · Inefficient

0.5–0.75 · OK

> 0.75 · Efficient

Source: Wall Street Prep / SaaS benchmarks (2025)

Why it matters for fast-growing companies

The magic number tells a funded startup whether to accelerate or pull back on go-to-market spend. Above 0.75 you can invest harder to grow without wasting cash; below 0.5 more spend just burns runway. It's the fastest gut-check on whether growth is buyable.

Frequently asked questions

What is a good SaaS magic number?+

Anything above 0.75 is considered efficient, meaning each dollar of sales and marketing is generating strong new ARR. Between 0.75 and 1.0 you have room to invest more aggressively. Below 0.5 signals the acquisition engine needs fixing before you add spend.

How is the magic number different from CAC payback?+

The magic number is a top-down efficiency ratio using total S&M spend and net-new ARR, so it's fast but blunt. CAC payback measures months to recover acquisition cost per customer using gross margin. Use the magic number to decide pace; use CAC payback for unit-level rigor.

SaaS magic number