SaaS Metrics

Unit Economics

Unit economics evaluate profitability and cash efficiency at the level of a unit (customer/account/order). Common unit metrics are CAC, LTV, and payback.

Updated 2026-01-23

Definition

Unit economics evaluate profitability and cash efficiency at the level of a unit (customer/account/order). Common unit metrics are CAC, LTV, and payback.

Example

A simple unit economics stack is: compute CAC, estimate LTV, sanity-check LTV:CAC, then confirm cash feasibility with CAC payback and runway.

How to use it

  • Pick a unit (customer/account) and keep definitions consistent.
  • Use gross profit (not revenue) when comparing to CAC.
  • Segment by channel/plan to avoid blended averages.

Common mistakes

  • Mixing fully-loaded CAC with revenue-only LTV (definition mismatch).
  • Using blended averages that hide unprofitable segments.

Measured as

Measure Unit Economics on the same customer segment, time window, and revenue basis each time you review it.

Misused when

  • Mixing fully-loaded CAC with revenue-only LTV (definition mismatch).
  • Using blended averages that hide unprofitable segments.

Operator takeaway

  • Pick a unit (customer/account) and keep definitions consistent.
  • Use gross profit (not revenue) when comparing to CAC.
  • Segment by channel/plan to avoid blended averages.
  • Keep Unit Economics consistent by cohort, segment, and period before you use it as a decision signal in planning or reporting.
  • Interpret the metric alongside retention, margin, or payback so one ratio does not hide the real operating trade-off.

Next decision

  • Quantify the impact with Unit Economics Calculator if you need to turn the definition into an operating assumption.
  • Read Unit economics: CAC, payback, LTV, and LTV:CAC (how to model them) if the decision depends on interpretation, policy, or trade-offs beyond the raw formula.

Where to use this on MetricKit

Calculators

Guides