Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Cumulative forecast revenue
$620,072
Current monthly revenue
$40,000
Projected ending monthly revenue
$63,160
Projected ending usage volume
78,950,211
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How to use this
- 1Enter current monthly usage volume (units).
- 2Enter price per 1,000 units ($).
- 3Enter monthly usage growth rate (%).
- 4Enter monthly account churn rate (fully stopped usage) (%).
- 5Enter forecast horizon (months).
- 6Read your cumulative forecast revenue on the right — it updates as you type.
- 7Hit Share to keep the scenario or send it to someone.
About this calculator
Usage-based pricing ties revenue directly to consumption (API calls, compute, data processed, messages sent), which means revenue forecasting looks more like a supply-chain or infrastructure model than a traditional seat-based SaaS forecast. This calculator projects revenue from current usage volume, an assumed usage growth rate, and price per unit, and layers in a simple churn-adjustment for accounts that stop using the product entirely versus those that keep growing consumption. Usage-based models tend to have higher revenue volatility than seat-based or flat-fee models because consumption can spike or drop with a customer's own business cycle, independent of any relationship health signal — a customer can be perfectly happy and still use less of your product in a slow month. This is why usage-based SaaS companies increasingly report both NRR and a 'net revenue retention excluding usage variance' metric internally, to separate genuine account health from short-term consumption noise.
Worked example
Using the values the calculator loads with:
Inputs
- Current monthly usage volume (units): 50000000
- Price per 1,000 units: 0.8 $
- Monthly usage growth rate: 6 %
- Monthly account churn rate (fully stopped usage): 2 %
- Forecast horizon: 12 months
Results
- Cumulative forecast revenue: $620,072
- Current monthly revenue: $40,000
- Projected ending monthly revenue: $63,160
- Projected ending usage volume: 78,950,211
What each field means
Inputs
- Current monthly usage volume (units)
- The current monthly usage volume (units) used in the calculation. Starts at 50000000 so you have a working example on load.
- Price per 1,000 units ($)
- The price per 1,000 units used in the calculation, measured in $. Starts at 0.8 $ so you have a working example on load.
- Monthly usage growth rate (%)
- The monthly usage growth rate used in the calculation, measured in %. Starts at 6 % so you have a working example on load. Accepted range: -50–100 %.
- Monthly account churn rate (fully stopped usage) (%)
- The monthly account churn rate (fully stopped usage) used in the calculation, measured in %. Starts at 2 % so you have a working example on load. Accepted range: 0–100 %.
- Forecast horizon (months)
- The forecast horizon used in the calculation, measured in months. Starts at 12 months so you have a working example on load. Accepted range: 1–60 months.
Results
- Cumulative forecast revenue
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Current monthly revenue
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Projected ending monthly revenue
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Projected ending usage volume
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Why apply account churn to a usage forecast?
Even in a usage-based model, some accounts stop entirely (contract ends, project shuts down, they migrate to a competitor), and that's different from an active account simply using less this month. Modeling churn separately from organic usage growth avoids over- or under-stating your baseline retention.
How volatile is usage-based revenue compared to seat-based?
Meaningfully more volatile month to month, since usage tracks a customer's own business activity (seasonality, project timelines, one-time migrations) rather than a relatively sticky headcount number. Forecast usage-based revenue with wider confidence bands and shorter re-forecast cycles than you would a seat-based model.
What pricing lever matters most for usage-based revenue growth?
Usually it's driving deeper product adoption within existing accounts (more use cases, more integrations) rather than raising per-unit price, since usage-based customers are price-sensitive to marginal cost by design and steep price hikes push them to optimize usage down rather than pay more.
Should I report ARR for a usage-based business the same way?
Many usage-based companies report ARR as annualized run-rate (current month times 12) rather than contracted ARR, since there may be no fixed contract minimum. Be explicit about which definition you're using — 'run-rate ARR' versus 'committed ARR' — because they can diverge significantly and investors will ask.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
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Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Usage-Based Revenue Forecast Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/usage-based-revenue-forecast
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/usage-based-revenue-forecast" target="_blank" rel="noopener">Usage-Based Revenue Forecast Calculator — RevenueLab</a> (2026).</p>
Source: [Usage-Based Revenue Forecast Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/usage-based-revenue-forecast) (2026).