METHOD & GUIDANCE
How this calculation works
Keep every input on the same time basis—for example, one month or one financial year—and do not mix cash figures with accrual figures. Tool IQ recalculates every output immediately; nothing you enter is saved or sent to us.
How to use the result
Compare the result with the cost of capital and a realistic alternative, then model a downside case with lower return or higher ongoing cost.
Worked example
The example invests 10,000, receives 14,500 and includes 500 of ongoing cost, leaving a 4,000 net gain and 40% ROI.
Common mistakes
- Ignoring ongoing or implementation cost.
- Comparing investments measured over different time periods.
- Treating an uncertain forecast as a guaranteed return.
Frequently asked questions
Is the roi calculator free?
Yes. It requires no account and stores no calculation inputs.
Can I use the answer for a formal filing?
No. It is a planning estimate, not accounting, tax, legal or investment advice. Confirm material decisions with a qualified professional.
Which period should I use?
Keep every input on the same basis—for example, one month or one financial year. Use current figures first, then save a cautious scenario for comparison.
Continue the decision
- Break-even Calculator — Find the sales volume needed to cover every cost.
- Profit Margin Calculator — See profit, margin and markup from one sale.
Popular small-business decision paths
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Method reviewed 5 August 2026. Figures are illustrative and calculated locally in your browser. Official sources are linked where a rule or obligation affects how the result should be used. Read the Tool IQ calculation standard for our checking process, limitations and corrections policy.