Business · Calculator companion · By K Imports
Return on investment: practical guide
This guide explains how to use the Count.ie return on investment. Calculate total and annualised net returns. Follow the inputs, method and worked example below, then compare your own scenario.
Guide written .
Open the Return on investment calculatorWhat to prepare
- Gather supplier quotes, invoices, time records and the actual scope of the job or business decision.
- Separate revenue from VAT, direct costs from overheads, and profit from the timing of cash receipts.
- Use the same accounting period and currency for related inputs.
Understand the inputs
The calculation method
ROI = net profit ÷ initial investment. Annualised return treats net proceeds as an end-of-period value.
Worked example
Illustrative inputs and their result.
Example inputs
- Initial investment (€)
- 10000
- Final sale / remaining value (€)
- 12000
- Income received (€)
- 1000
- Additional costs (€)
- 500
- Holding years
- 3
Calculated example result
- Roi Percent
- 25%
- Net Profit
- €2,500.00
How to interpret the result
A profitable estimate can still create a cash shortfall. Read the cost and timing assumptions as well as the headline profit, price or return; the result is a scenario, not a sales forecast.
Keep the scope constant while changing price, volume, supplier cost or time. A lower-sales or higher-cost case helps show whether the decision depends on an optimistic assumption.
Common mistakes to avoid
- Do not confuse markup on cost with margin on selling price.
- Include work that is easy to miss, such as travel, setup, rework and administration, where the model supports it.
- Do not treat tax collected or an unpaid invoice as freely available cash.
Assumptions and sources
The model is not IRR for multiple cash-flow dates. Include relevant tax and fees in costs.
If your case falls outside this scope, use a more suitable calculator or contact us about an unclear method.