ROI Calculator
Use ROI Calculator to calculate return on investment — free, immediate, and with nothing to install. Every figure is worked out on your own device using standard formulas — nothing you type is transmitted, which matters when the numbers are your salary, loan or health data. It is used most by students checking homework answers step by step. Both metric and imperial units are supported where relevant. It stays free with unlimited use, and there is no watermark on anything it produces.
Key features
- Both metric and imperial units are supported where relevant.
- Results update as you type, so you can see the effect of changing one figure.
- Works on desktop, tablet and phone — no separate app to install.
- No ads interrupting the tool itself, and no upsell before the result.
How to use ROI Calculator
- Enter your figures: Fill in the fields above. Leave anything optional blank and a sensible default is used.
- Pick your units: Switch between metric and imperial if the calculation involves units.
- Read the result: The answer updates immediately, with the breakdown shown so you can check the working.
Frequently asked questions
- Is there a limit on how often I can use it? — No. It is free and unlimited, with no account required.
- Why does my answer differ from another site? — Usually a different formula variant or rounding step. Check the inputs match before assuming one is wrong.
- Are my numbers sent anywhere? — No. The calculation runs in your browser. Salary, loan and health figures never leave the device.
- How accurate is ROI Calculator? — ROI Calculator uses the standard published formula for this calculation with full double-precision arithmetic, so the arithmetic itself is exact. Accuracy of the answer depends on the figures you enter.