SaaS Metrics

LTV (Lifetime Value)

LTV estimates the value a customer generates over their lifetime. For unit economics, gross profit LTV is usually more useful than revenue LTV.

Updated 2026-01-23

Definition

LTV (Lifetime Value) is the total value you expect from a customer over their lifetime. It's often used to set acquisition targets (CAC/CPA) and to evaluate payback and growth efficiency. Because costs matter, many teams prefer gross profit LTV (revenue * gross margin over the lifetime).

Common formulas (shortcuts)

  • Revenue LTV ~ ARPA / churn (with consistent time units).
  • Gross profit LTV ~ (ARPA * gross margin) / churn.
  • Cohort-based LTV: sum observed gross profit over time from real cohorts (more accurate).

Example

If ARPA is $500/month, gross margin is 80% (0.8), and monthly churn is 2% (0.02), then gross profit LTV ~ ($500 * 0.8) / 0.02 = $20,000.

Common mistakes

  • Using revenue LTV while comparing to fully-loaded CAC (mismatch).
  • Mixing monthly churn with annual ARPA (time unit mismatch).
  • Ignoring expansion or contraction when it materially affects retention dynamics.

Measured as

Measure LTV (Lifetime Value) on the same customer segment, time window, and revenue basis each time you review it.

Misused when

  • Using revenue LTV while comparing to fully-loaded CAC (mismatch).
  • Mixing monthly churn with annual ARPA (time unit mismatch).
  • Ignoring expansion or contraction when it materially affects retention dynamics.

Operator takeaway

  • Keep LTV (Lifetime Value) 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 LTV Calculator if you need to turn the definition into an operating assumption.
  • Read LTV: How to estimate Lifetime Value (and when not to) if the decision depends on interpretation, policy, or trade-offs beyond the raw formula.

Where to use this on MetricKit

Calculators

Guides