AI Startup Unit Economics Calculator (gross margin, LTV:CAC with model costs)

How it works

Variable cost per user = AI requests × cost per request + hosting + payment fees. Gross margin = price − variable cost. Average customer lifetime = 1 ÷ monthly churn, so LTV = monthly gross margin ÷ churn. LTV:CAC compares lifetime margin with what it costs to win a customer; CAC payback = CAC ÷ monthly gross margin. The last row shows how heavy a user can be before they cost more than they pay — useful for setting usage limits.

⚠ Estimates for information only — not financial advice.

FAQ

Why do AI products have lower margins than classic software?

Every request costs money for model inference, so heavy users can cost more than they pay. Track AI cost per user and set limits or usage-based pricing.

What LTV:CAC is healthy?

Many investors look for about 3× or more with a CAC payback within a year or so, but the right target depends on your growth stage and cash.

Checked 10 Nov 2026. Standard SaaS unit economics: customer lifetime = 1 ÷ churn rate, LTV = gross margin per period ÷ churn, CAC payback = CAC ÷ gross margin per period (e.g. D. Skok, “SaaS Metrics 2.0”).