About the SaaS Magic Number Calculator
The SaaS magic number measures how much new annualized recurring revenue each dollar of sales and marketing (S&M) spend produces. Enter revenue for the latest two quarters and S&M spend from the earlier quarter, and the calculator gives the magic number, a gross-margin-adjusted version, an implied CAC payback and a plain-English verdict.
Revenue leaders and CFOs use it to decide whether to step on the gas: a magic number above about 0.75 usually suggests adding sales capacity, while one below 0.5 suggests fixing the go-to-market engine first. Investors use it to compare efficiency across companies of different sizes.
The prior quarter’s spend is used because deals take time to close. You can enter quarterly GAAP revenue (annualized by ×4) or ARR at each quarter end (no annualization needed). The metric assumes revenue growth comes mainly from S&M activity rather than price changes or one-off items.
With the default inputs, the magic number is 0.8. Change any value above to recalculate instantly.
How to use the saas magic number calculator
- 1Choose whether you are entering quarterly revenue or quarter-end ARR.
- 2Enter this quarter’s and last quarter’s figures.
- 3Enter last quarter’s total sales and marketing spend.
- 4Enter gross margin for the margin-adjusted view.
- 5Use the verdict to decide whether to scale, optimize or fix go-to-market.
Formula and method
The magic number annualizes the quarter-over-quarter revenue increase (multiplying by four) and divides it by the previous quarter’s sales and marketing expense, reflecting the lag between spending and closing deals. If you use ARR, the difference is already annual, so no multiplier is applied.
Multiplying by gross margin converts new revenue into new gross profit, a stricter view of efficiency. Twelve divided by that figure approximates how many months of gross profit it takes to recover the S&M investment. The verdict uses the commonly cited 0.5 and 0.75 thresholds.
- Rev_q
- Revenue in the latest quarter
- Rev_q−1
- Revenue in the previous quarter
- S&M_q−1
- Sales and marketing expense in the previous quarter
Worked examples
Quarterly revenue up $300k
Revenue rose from $2.3M to $2.6M, or $1.2M annualized. Divided by $1.5M of prior-quarter S&M that is a 0.8 magic number, or 0.6 after a 75% gross margin — about 20 months to recover spend.
Using ARR
ARR grew $1.5M in the quarter on $2M of prior-quarter S&M, a magic number of 0.75. At 80% gross margin the adjusted figure is 0.6.
Spending ahead of results
A $100k quarterly revenue gain annualizes to $400k, only 0.2 per dollar of S&M. After a 70% margin it would take about 86 months to earn back the spend.
Frequently asked questions
What is a good SaaS magic number?+
Above about 0.75 is generally considered efficient enough to invest more in sales and marketing; 0.5–0.75 suggests optimizing; below 0.5 means growth is expensive and the go-to-market engine needs work. Above 1 is excellent.
Why use the previous quarter’s S&M spend?+
Sales cycles mean money spent this quarter mostly produces revenue next quarter. Pairing current revenue growth with prior-quarter spend better matches cause and effect.
Should I use revenue or ARR?+
Either is acceptable. GAAP revenue is easy to pull from financial statements; ARR reflects contracted run rate and is more common in private SaaS. Be consistent over time.
How is the magic number related to CAC payback?+
They are two views of the same efficiency. The gross-margin-adjusted magic number tells you gross profit per dollar of S&M per year, so 12 divided by it approximates CAC payback in months.
Results are estimates for educational purposes and are not financial advice. Rates, fees and terms vary — confirm with your lender or a licensed advisor before making decisions.