ROI Calculator
Measure the return on an investment, including the annualised rate over time.
Free No signup Runs in your browser — nothing uploaded
€
€
years
- ROI
- 40.00%
- Net gain
- € 400.00
- Annualised return
- 40.00%
What it does
ROI Calculator shows the whole calculation, not just the answer: every intermediate figure is on screen, so you can check it against your own numbers instead of trusting a single output box.
When you need it
Quoting, invoicing, or checking someone else's arithmetic — the moments where being roughly right costs money, and where the formula is easy to get subtly backwards.
Limits and caveats
Figures are unrounded until the final display, so results will not always match a calculation that rounded at each step. This is a working tool, not tax or financial advice, and local rules may differ. Everything happens in your browser, so the file never leaves your device.
How to use the ROI Calculator
- Enter your numbers.
- Results update as you type.
- No rounding surprises — the maths is shown in full.
Frequently asked questions
- Why does annualised return matter?
- A 40% return over five years is very different from 40% in one year — annualising makes them comparable.