SaaS ROI: Know Your ROAS Before Spending on Ads — SmartToolKit Lab
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SaaS ROI: Know Your ROAS Before Spending on Ads

Marketing · 4 min read

Most SaaS founders launch ad campaigns on gut feeling. Four numbers tell you in advance whether the math works:

1. CAC (Customer Acquisition Cost)

Ad spend ÷ customers acquired. If you spend $1,000 and get 40 customers, your CAC is $25.

2. Gross profit per customer

Average revenue per customer × gross margin. At $79 ARPC and 80% margin, each customer is worth $63.20 in gross profit.

3. ROAS and ROI

ROAS = revenue ÷ ad spend. ROI = (gross profit − ad spend) ÷ ad spend. Positive ROI means the campaign pays for itself — everything above is growth.

4. Break-even point

Ad spend ÷ gross profit per customer = the number of customers you need to not lose money. In our example: $1,000 ÷ $63.20 ≈ 16 customers.

Run your own numbers — free:

Open ROI Calculator →
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