ROI Calculator
Calculate return on investment and the annualised return.
Your result
Updates as you type. Based on 2025/26 UK figures where relevant.
How this is worked out
ROI = (final value − amount invested) ÷ amount invested. Annualised return = (final ÷ invested)^(1 ÷ years) − 1.
Tips
- Price from margin, not markup, if you want to hit a target profit percentage.
- Quote prices to businesses ex VAT and to consumers inc VAT.
- You can legally claim statutory interest on late B2B invoices.
Guides for this calculator
- How to Calculate Return on Investment in the UK: Step-by-Step Guide
- Return on Investment: Common Mistakes, Tips and FAQs
More business calculators
Frequently asked questions
How does the rOI Calculator work?
ROI = (final value − amount invested) ÷ amount invested. Annualised return = (final ÷ invested)^(1 ÷ years) − 1.
Are statutory pay figures up to date?
Rates are editable on each calculator. Defaults reflect recent published rates; always confirm current figures on GOV.UK.
Do these work for sole traders?
Yes. Margin, markup and break-even apply to any business size.
Is this legal advice?
No. For disputes about pay, redundancy or debts, contact Acas, Citizens Advice or a solicitor.
This calculator gives an estimate for general information. It isn't financial, tax, legal or medical advice. Check official figures on GOV.UK or NHS.uk, or speak to a qualified adviser.