Calculate MRR, ARR, churn, LTV and CAC in one free SaaS spreadsheet
Recurring-revenue businesses are not understood properly by looking at sales alone.
A SaaS company can add customers every month and still struggle if churn removes customers too quickly, customer acquisition costs are too high or the value generated by each customer is too low.
The free SaaS Metrics Calculator Excel template turns six operating assumptions into a 12-month customer and recurring-revenue build, together with key SaaS metrics including MRR, ARR, customer lifetime value, CAC and LTV:CAC ratio.
It is designed as a simple one-sheet calculator for founders who want to understand the core economics of a subscription business without building a complete SaaS financial model first.
What problem does the SaaS Metrics Calculator solve?
A headline revenue forecast can hide the mechanics underneath a SaaS business.
Recurring revenue depends on the movement of customers through the subscription base.
Each month:
- existing customers begin the period; - some customers churn; - new customers are acquired; - the remaining customer base generates recurring revenue.
The free calculator models that process month by month.
This makes it possible to see how a churn assumption affects the customer base and MRR rather than treating revenue growth as an unexplained percentage.
What inputs does the free SaaS calculator use?
The workbook uses inputs for:
- starting customers; - new customers per month; - monthly churn percentage; - average revenue per customer per month (ARPU); - gross margin percentage; - monthly marketing and sales spend.
These assumptions drive the 12-month customer and recurring-revenue calculation.
What does the SaaS Metrics Calculator calculate?
The spreadsheet calculates:
- customers at the start of each month; - churned customers; - new customers; - customers at the end of each month; - monthly recurring revenue (MRR); - ending MRR; - annual recurring revenue (ARR); - net new MRR; - customer lifetime value (LTV); - customer acquisition cost (CAC); - LTV:CAC ratio.
The calculations update automatically when the input assumptions are changed.
MRR calculator
Monthly Recurring Revenue (MRR) is one of the fundamental SaaS metrics.
The calculator takes the projected customer base and average monthly revenue per customer and uses them to calculate recurring revenue across the 12-month period.
This allows founders to see how customer acquisition and churn affect MRR over time.
Someone searching for a free MRR calculator Excel template can therefore use this workbook to model the relationship between customers and recurring revenue rather than entering MRR manually.
ARR calculator
Annual Recurring Revenue (ARR) provides an annualised view of recurring revenue.
The calculator derives ending ARR from Month 12 MRR, allowing the user to see the recurring-revenue run rate produced by the customer assumptions.
This provides a simple MRR and ARR calculator in the same spreadsheet.
SaaS churn calculator
Churn can materially change a subscription forecast.
Adding 15 new customers each month does not mean the customer base increases by 15 if existing customers are cancelling at the same time.
The workbook removes churn before adding the new customers for each monthly cohort calculation.
Changing the monthly churn assumption therefore updates the customer base and recurring-revenue forecast automatically.
This makes the spreadsheet useful for testing questions such as:
- What happens to MRR if churn increases? - How much does lower churn improve the Month 12 customer base? - Are new customer additions enough to offset cancellations? - How sensitive is recurring revenue to retention?
SaaS LTV calculator
Customer Lifetime Value (LTV) is intended to estimate the economic value of a customer relationship.
The calculator uses the relevant revenue, gross-margin and churn assumptions to calculate an LTV metric.
This helps connect customer retention to customer economics.
A lower churn rate can increase expected customer lifetime and therefore change estimated LTV.
CAC calculator
Customer Acquisition Cost (CAC) measures the cost associated with acquiring new customers.
The workbook uses monthly marketing and sales expenditure together with customer acquisition assumptions to calculate CAC.
This makes it possible to compare acquisition cost with estimated customer value rather than looking at marketing spend in isolation.
LTV:CAC ratio
The relationship between customer lifetime value and acquisition cost is a widely used SaaS unit-economics measure.
The free calculator produces an LTV:CAC ratio so the user can see how the estimated value of a customer compares with the cost of acquiring one.
Changing churn, ARPU, gross margin, marketing spend or customer acquisition changes the relevant economics.
Who is this free SaaS metrics spreadsheet for?
The calculator is designed for:
- SaaS founders; - subscription-business owners; - startup teams; - founders preparing early financial assumptions; - people evaluating recurring-revenue economics; - users searching for a simple SaaS metrics spreadsheet free download; - businesses that want to calculate MRR, ARR, churn, LTV and CAC without building the formulas from scratch.
Use it for SaaS scenario analysis
The calculator becomes particularly useful when assumptions are changed.
You can test:
- higher or lower monthly churn; - more new customers each month; - different ARPU; - changes in gross margin; - higher or lower marketing spend.
The customer build and key metrics update from those assumptions.
This makes the workbook a useful first-stage SaaS unit economics calculator rather than merely a static KPI sheet.
What this free SaaS calculator does not do
The workbook is deliberately a lightweight lead-in tool.
It does not attempt to replace a full SaaS financial model with detailed operating expenses, hiring, cash flow, funding and broader financial statements.
Its purpose is narrower: make the core customer and recurring-revenue mechanics visible quickly.
Need a complete SaaS financial model?
For a more detailed forecast, the SaaS Financial Model in the JEBS financial-model catalogue extends the analysis into a broader business forecast.
The free calculator is intended for understanding core MRR, ARR, churn, LTV and CAC mechanics.
The full SaaS model is intended for users who need a more complete financial-planning tool.
The same cohort-style customer logic can also be relevant to membership businesses. JEBS also provides a Fitness Studio & Gym Membership Model built specifically around joins, churn, membership revenue, break-even members, LTV and CAC payback.
Download the free SaaS Metrics Calculator
The SaaS Metrics Calculator is available as a free Excel download from James Edison Business Solutions.
Enter your own customer, churn, ARPU, margin and acquisition assumptions and use the workbook to calculate a 12-month customer build, MRR, ARR, LTV, CAC and LTV:CAC ratio.
Download the Free SaaS Metrics Calculator →
Important
This calculator is a financial modelling and business-planning template. It is not financial, investment, accounting, tax or legal advice. SaaS metrics can be defined differently between businesses and analyses. Verify the definitions and assumptions appropriate to your business before relying on the results.