What is SaaS Magic Number?
A quick gauge of go-to-market efficiency - how much new recurring revenue each sales-and-marketing dollar buys.
SaaS Magic Number: definition
The magic number connects go-to-market spend to the revenue it produces, with a one-quarter lag to reflect the time between spending and closing. A result of 1.0 means one dollar of sales and marketing generated one dollar of new annual recurring revenue - efficient enough to justify pressing on the accelerator. Below about 0.5 suggests spending is inefficient and should be examined before scaling.
SaaS magic number
Magic Number = (New ARR this quarter) ÷ (S&M spend last quarter)
Often computed as (change in quarterly revenue × 4) ÷ prior-quarter S&M. Above 0.75 is generally healthy; above 1.0 is strong.
How Fintra handles it
Because Fintra holds both recurring revenue and sales and marketing spend, the magic number can be computed from actuals with the correct one-quarter lag, rather than pieced together across tools. It sits alongside CAC, payback, and the Rule of 40 so go-to-market efficiency is judged in context, and planning shows how added spend is likely to convert.
- Magic number computed from actual new ARR and prior-quarter S&M
- Shown with CAC, payback, and Rule of 40
- Planning tests how incremental S&M spend converts to ARR
Worked example
Frequently asked questions
What is a good SaaS magic number?
Above 0.75 is generally considered efficient, and above 1.0 is strong - it means growth pays for itself quickly, justifying more investment. Below about 0.5 suggests go-to-market spending is inefficient and the model should be examined before scaling further.
Why does the magic number use a one-quarter lag?
Because sales and marketing spend takes time to convert into closed revenue. Comparing this quarter new revenue to last quarter spend better reflects the cause-and-effect delay in the go-to-market motion than comparing the same quarter figures.
What are the limitations of the magic number?
It is a coarse, blended measure that ignores expansion versus new business, sales-cycle length, and cohort quality. It also assumes a consistent lag. Use it as a directional efficiency signal alongside CAC, payback, and retention rather than as a precise verdict.
How is the magic number different from LTV:CAC?
The magic number is a fast, top-down measure of blended sales efficiency using aggregate spend and revenue. LTV:CAC is a per-customer, bottom-up measure of acquisition value. They can point in the same direction, but LTV:CAC is more granular while the magic number is quicker to compute.
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