How to calculate ROI
ROI Calculator computes roi directly in your browser. It is built for comparing investment returns and uses (final - initial) / initial, annualised based on the inputs you provide.
Photo: Carlos Muza on Unsplash
What this calculator computes
| Topic | ROI |
| Category | Business & SaaS |
| Inputs | MRR, ARR, churn, customer count |
| Output | LTV, CAC payback, runway |
| Math model | SaaS unit economics formulas |
| Best for | Founders sizing SaaS or service businesses |
| Cost | Free, no login, in browser |
Step by step
Open ROI Calculator
Visit /tools/roi-calculator in any modern browser. The tool loads instantly and runs entirely on your device, so no inputs are transmitted to a server.
Gather your inputs
Have your initial investment, final value, holding period ready. Accuracy on the output depends entirely on the quality of these numbers. If a value is uncertain, use the most realistic figure rather than rounding aggressively.
Enter the values
Fill each field in turn. ROI Calculator validates ranges as you type, so an obvious typo (for example a negative balance where one cannot exist) will flag immediately.
Read the result
The output is a roi percentage, annualised roi, computed using (final - initial) / initial, annualised. Treat it as a precise answer to the question you posed, not an approximation.
Verify and compare
Re-run the calculation with a slightly different input to test sensitivity. For deeper comparison against another approach, see related tools in the Business & SaaS hub or pick a related roi tool below.
When to use ROI Calculator
- Modelling runway under a new spend plan
- Comparing two pricing models on the same cohort
- Sizing payback on a customer acquisition campaign
Frequently asked questions
What does ROI Calculator compute?
ROI Calculator computes a roi percentage, annualised roi from initial investment, final value, holding period, using (final - initial) / initial, annualised.
Is ROI Calculator free?
Yes. It is free, runs in your browser, requires no login, and does not transmit your inputs to any server.
What inputs do I need to use ROI Calculator?
You need initial investment, final value, holding period. Accuracy depends entirely on the inputs you provide.
When should I use ROI Calculator?
Use it when your task is comparing investment returns and you need a quick, deterministic answer for a roi question.
Where can I find related tools?
Browse the full Business & SaaS category for tools that share the same inputs or solve adjacent problems.
Keep exploring
- Open ROI Calculator
- Browse the Business & SaaS category hub
- See comparison pages that include this tool on the compare index