Fixture v0 · static · no accounts

Subscription churn calculator

Sensitivity check for monthly subscription LTV, LTV:CAC, and payback. Change the inputs; formulas stay visible below.

Inputs

Monthly price (ARPU) EXAMPLE Revenue per subscriber per month before churn

Monthly churn EXAMPLE Percent of customers lost each month

CAC EXAMPLE Fully loaded cost to acquire one subscriber

Horizon (months) EXAMPLE Finite window for horizon LTV (geometric retention)

Classic LTV

—

price ÷ monthly churn rate

Horizon LTV

—

retained revenue over N months

LTV : CAC

—

using classic LTV

Payback months

—

CAC ÷ monthly price (gross)

Monthly churn rate r = churn% ÷ 100
Classic LTV (infinite simple SaaS model) LTV = price ÷ r when r > 0. If churn is 0, classic LTV is treated as unbounded for this fixture.
Horizon LTV (finite geometric retention) LTV_N = price × (1 − (1 − r)^N) ÷ r for r > 0; if r = 0, LTV_N = price × N.
LTV:CAC ratio = classic LTV ÷ CAC (uses classic LTV so the ratio is comparable to common SaaS benchmarks).
Gross payback months payback = CAC ÷ price (months to recover CAC at full monthly ARPU; ignores churn and margin).

Assumptions for this fixture: