Unit Economics and Profitability

Unit Economics: Do You Make Money on Each Customer?

Unit economics answers a single critical question: for every customer you acquire, do you make more money than you spend?

A business with poor unit economics cannot be fixed by growing faster. Growth accelerates losses. Fix unit economics first, then grow.

Gross Margin

Gross margin measures how much revenue remains after the direct costs of delivering the product.

Costs of Goods Sold (COGS) for SaaS: hosting and infrastructure, third-party API costs (AI API credits, email, SMS), payment processing fees, customer support cost per customer.

Good SaaS gross margins:

• Traditional SaaS: 70-85%
• AI-powered SaaS: 40-65% (AI API costs are significant)
• Marketplace: 20-40%

The AI Cost Challenge

AI applications often have lower gross margins because each user interaction consumes API tokens that cost money. On a $49/month plan, AI API costs of $8-12/month can significantly reduce margins.

Improving Unit Economics

• Increase ARPU: Upsell to higher tiers, usage-based pricing for heavy users
• Decrease AI API costs: Use cheaper models for simple tasks, cache responses, set token limits per tier, batch requests
• Decrease churn: Improve onboarding, increase feature adoption
• Decrease CAC: Invest in content marketing, build referral programs

Contribution Margin

Contribution margin = (monthly revenue - variable costs) / monthly revenue. If negative, every new customer makes you poorer. Fix before scaling.

The Path to Profitability

The critical question: could you be profitable if you stopped growing? If yes, you have a viable business choosing to invest in growth. If no, fix the cost structure problem first — growth will make it worse.

Key Takeaways

• Gross margin for SaaS should be 70-85%; AI-heavy products often land at 50-65% due to API costs
• AI API costs are significant and variable — model selection, caching, and usage limits are direct levers
• If contribution margin is negative, stop growing — every new customer loses money
• The path to profitability question: "Could we be profitable if we stopped growing?"
• Improving unit economics: increase ARPU, decrease COGS, decrease churn, decrease CAC