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Written by MetricKit EditorialReviewed by MetricKit Editorial ReviewUpdated 2026-06-20
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MRR Forecast Calculator: Monthly Projection, Formula, and Example

Project future MRR using new MRR, expansion, contraction, churn, and time horizon inputs with a simple monthly forecast model.

This MRR forecast calculator projects monthly recurring revenue using a simple bridge model of starting MRR, new MRR, expansion, contraction, and churn.

Use it when you need a planning answer to a practical question: if current acquisition and retention assumptions continue, where does recurring revenue land and what part of the bridge deserves the next decision.

Prefer an explanation- Read the guide.
Related definitions:arrmrrnet new mrrnew mrrexpansion mrrcontraction mrrchurned mrrnrrgrrcmgr
MRR Forecast Formula: Example, Template, and Monthly BridgeRevenue retention curves: GRR vs NRR over time (how to model)NRR vs GRR: differences, formulas, and how to use bothRetention & churn hub: cohorts, GRR/NRR, and retention curves
 
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Recurring revenue from brand-new customers (not expansions).
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%
 
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Tip: you can type commas (e.g., 10,000).
Next action

Use the projection as a planning signal, then inspect retention quality

A rising MRR forecast does not automatically mean the revenue engine is healthy. Use the forecast guide to interpret the bridge, then move to an MRR waterfall or NRR/GRR analysis if new MRR may be hiding weak existing-customer retention.

Read the MRR forecast guideCheck the MRR waterfall next

Example

Using the default inputs, the result is:
$244,000.00
Starting MRR
$100,000
New MRR added per month
$12,000
Monthly expansion rate (existing MRR)
2%
Monthly contraction rate (existing MRR)
0.5%
Monthly churn rate (existing MRR)
1.5%
Months to forecast
12

How to calculate

  1. Enter your starting MRR (current recurring run-rate).
  2. Estimate new MRR added per month (from new customers).
  3. Set monthly expansion, contraction, and churn rates for existing MRR.
  4. Choose a horizon (e.g., 6-24 months) and compare scenarios.

Formula

Ending MRR = iterate monthly: MRR_next = MRR + new + (expansion% * MRR) - (contraction% * MRR) - (churn% * MRR)
  • Rates apply to the current month's MRR base (not cohort-based).
  • New MRR is constant each month for simplicity.
  • This is a planning model; use cohort retention curves for higher precision.

Benchmarks

  • A strong ending MRR can still be fragile if implied NRR or GRR is weak and the model depends too heavily on new MRR.
  • If month-6 or month-12 MRR only looks healthy under one narrow assumption set, treat the forecast as directional planning input rather than operating certainty.
  • Use the projection for planning, then use an MRR waterfall, NRR, and GRR to understand whether existing-customer health supports the headline path.

FAQ

Is this the same as NRR forecasting-
This model includes both new customer growth (new MRR) and existing customer dynamics (expansion, contraction, churn). NRR focuses only on existing customers; here we show the implied monthly NRR from your assumptions.
What horizon should I use-
For execution planning, 6-12 months is common. For longer-range strategy, use scenarios (base/optimistic/conservative) because small rate changes compound quickly.

Common mistakes

  • Mixing time units (monthly churn with annual inputs).
  • Using expansion/churn rates that imply impossible outcomes (e.g., churn > 100%).
  • Treating this as a replacement for cohort-based retention curves; use cohorts for higher accuracy.
  • Trusting projected ending MRR without checking whether the bridge is being carried by new MRR while NRR or GRR is weakening.

Related calculators

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Calculate Customer Acquisition Cost (CAC) from total acquisition spend and new customers.
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Calculate fully-loaded CAC by including paid spend plus sales & marketing costs (salaries, tools, and other acquisition costs).
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LTV Calculator
Estimate customer Lifetime Value (LTV) using ARPA, gross margin, and churn rate.
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LTV Sensitivity Calculator
See how gross profit LTV changes as churn and gross margin vary (simple 3x3 sensitivity).
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LTV:CAC Calculator
Compute LTV:CAC ratio and CAC payback using ARPA, gross margin, churn, and CAC.
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CAC Payback Period Calculator
Estimate how many months it takes to recover CAC (months to recover CAC) using gross profit.

Quick checks

  • Keep time units consistent (monthly vs annual) across inputs and outputs.
  • Segment by cohort/channel/plan before trusting a blended average.
  • Use the related guide to avoid common definition and denominator mismatches.