ROI Calculator
Calculate Return on Investment percentage.
Input & results
Input values
Results
Enter values to see instant results.
Calculation History
- Your calculations will appear here.
Recent calculations are saved automatically as you adjust inputs.
Financial results are estimates for informational purposes only and are not financial, tax, or investment advice. Verify figures with a qualified professional before making decisions. See our full disclaimer.
What is ROI?
The ROI Calculator is a free online tool that helps you calculate return on investment percentage. It applies the standard roi formula to your inputs and returns results instantly, with no spreadsheets or manual math required.
Built for founders, operators, and finance teams, this calculator turns Gain from Investment, Cost of Investment into a clear result you can act on. Every calculation runs privately in your browser, so your figures stay on your device. The page also explains the formula, defines each variable, and walks through a worked example so you understand exactly how the answer is derived.
Why is it used?
People use the ROI Calculator to track growth, efficiency, and runway with confidence. It removes guesswork from startup metrics and SaaS unit economics, lets you compare scenarios in seconds, and helps avoid the rounding and formula errors that creep into manual or spreadsheet calculations.
Who should use it?
This calculator is ideal for founders, operators, and finance teams working through startup metrics and SaaS unit economics. Whether you are planning ahead, double-checking a figure, or learning how roi works, it gives dependable results in seconds.
How it works
- Enter Gain from Investment, Cost of Investment in the input fields.
- The calculator validates your entries and applies the correct roi formula.
- Results update in real time as you change any value — no submit button needed.
- Review the formula, variable definitions, and worked example below to see how the answer is derived.
Formula
ROI (%) = ((Gain − Cost) ÷ Cost) × 100
Variable definitions
| Variable | Meaning |
|---|---|
| Gain | Total return or revenue from the investment |
| Cost | Initial investment or cost basis |
How the formula works
- Subtract cost from gain to get net profit
- Divide net profit by cost
- Multiply by 100 to express as a percentage
Example calculation
ROI on ₹50,000 investment returning ₹65,000
| Input | Value |
|---|---|
| gain | ₹65,000 |
| cost | ₹50,000 |
Result
Methodology
- Gather Gain from Investment, Cost of Investment from your documents or estimates.
- Enter each value in the matching field; units must match the labels.
- The calculator applies the ROI formula and updates results in real time.
- Compare scenarios by changing one input at a time.
Benefits
- Instant roi results with no manual calculation.
- Fewer errors than spreadsheets or handheld calculators.
- Compare multiple scenarios in seconds by adjusting inputs.
- Free and private — calculations run on your device, no account needed.
Use cases
- Planning startup metrics and SaaS unit economics before making a decision.
- Double-checking figures from invoices, statements, or spreadsheets.
- Learning how roi is calculated, step by step.
- Comparing options quickly to find the best outcome.
Tips & important notes
- Confirm units match the field labels (e.g. months vs years, % vs decimal).
- Start with realistic baseline values, then adjust one input at a time.
- Cross-check important results with an official source or advisor.
- Use the copy button on results to save outputs for your records.
Common mistakes
- Mixing annual and monthly values (e.g. rate per year vs tenure in months).
- Entering a percentage as a whole number when a decimal is expected, or vice versa.
- Ignoring fees, taxes, or rounding rules that apply on top of the base formula.
Related concepts
- The core roi formula and what each variable means
- Unit conversions relevant to Gain from Investment, Cost of Investment
- Related calculators in the startup-saas category on Calcmate.live
Good to know