SaaS MRR, Churn, LTV & CAC Calculator

Model your recurring subscription growth. Calculate Net New MRR, Net Dollar Retention (NDR), gross monthly churn rate, implied Customer Lifetime Value (LTV), LTV:CAC ratio and CAC payback months.

Monthly Waterfall Numbers

Starting MRR ($)

New Customer MRR ($)

Expansion / Upgrade MRR ($)

Churned / Lost MRR ($)

ARPU ($ / User / Mo)

Customer Acquisition Cost / CAC ($ per new customer)

Sales + marketing spend ÷ new customers won in the same period.

SaaS Unit Economics

Ending MRR

$29,600

Run-Rate (ARR)

$355,200

Net New MRR:+$4,600

Monthly Churn Rate:4.40%

Net Dollar Retention (NDR):100.4%

Avg Customer Lifespan:22.7 months

Implied Customer LTV:$1800

LTV : CAC Ratio:4.0x

CAC Payback Period:5.7 months

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SaaS MRR Waterfall & Cohort Retention Tracker

Track new, expansion, contraction and churned MRR month by month, with gross churn, net dollar retention and a cohort retention heatmap.

100% Macro-Free (.xlsx) • Native dynamic formulas

Single-user perpetual license • Zero monthly SaaS

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