METHOD & GUIDANCE
How this calculation works
Enter figures from the same period and on a consistent VAT-inclusive or VAT-exclusive basis. 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 this 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.
Should I include VAT?
Use a consistent basis throughout. Businesses that recover input tax commonly model net figures; consumer-facing prices are often considered gross.
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.
Method reviewed 26 July 2026. Figures are illustrative and calculated locally in your browser.