CAC vs LTV Calculator

Check if your unit economics work before scaling your acquisition spend.

Total marketing + sales spend last month ($)

New customers acquired last month

Average monthly revenue per customer ($)

Your ARPU — average monthly subscription or purchase value per customer.

Average customer lifespan (months)

If monthly churn is 5%, average lifespan is 1/0.05 = 20 months.

Gross margin (%)

SaaS businesses typically run 70–80% gross margin. Default 70%.

Results

CAC — Customer Acquisition Cost$200.00

LTV — Lifetime Value$1,680.00

LTV:CAC Ratio8.4x

Healthy

An LTV:CAC ratio above 3x is the industry benchmark for a sustainable SaaS business. You're acquiring customers for a fraction of what they're worth. Focus on growth.

Rule of thumb: LTV:CAC above 3x is healthy for SaaS. Below 1x means you lose money on every customer — no amount of growth fixes that.

Levers to improve: reduce churn (raises LTV), increase ARPU (raises LTV), or find cheaper acquisition channels (lowers CAC).

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