body {
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
line-height: 1.6;
color: #333;
max-width: 800px;
margin: 0 auto;
padding: 20px;
}
.calculator-container {
background: #f8f9fa;
border: 1px solid #e9ecef;
border-radius: 8px;
padding: 30px;
margin-bottom: 40px;
box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}
.calc-header {
text-align: center;
margin-bottom: 25px;
color: #2c3e50;
}
.form-group {
margin-bottom: 20px;
}
.form-group label {
display: block;
margin-bottom: 8px;
font-weight: 600;
color: #495057;
}
.form-group input {
width: 100%;
padding: 12px;
border: 1px solid #ced4da;
border-radius: 4px;
font-size: 16px;
box-sizing: border-box;
}
.form-group input:focus {
border-color: #28a745;
outline: none;
box-shadow: 0 0 0 3px rgba(40, 167, 69, 0.25);
}
.calc-btn {
width: 100%;
background-color: #28a745;
color: white;
border: none;
padding: 15px;
font-size: 18px;
font-weight: bold;
border-radius: 4px;
cursor: pointer;
transition: background-color 0.2s;
}
.calc-btn:hover {
background-color: #218838;
}
.results-box {
background: #fff;
border: 1px solid #dee2e6;
border-radius: 4px;
padding: 20px;
margin-top: 25px;
display: none;
}
.result-row {
display: flex;
justify-content: space-between;
padding: 10px 0;
border-bottom: 1px solid #eee;
}
.result-row:last-child {
border-bottom: none;
}
.result-label {
color: #6c757d;
}
.result-value {
font-weight: bold;
font-size: 1.1em;
color: #2c3e50;
}
.excel-code-block {
background-color: #2b2b2b;
color: #a9b7c6;
padding: 15px;
border-radius: 4px;
font-family: monospace;
margin-top: 15px;
word-break: break-all;
}
.excel-label {
font-size: 12px;
color: #666;
text-transform: uppercase;
letter-spacing: 1px;
margin-top: 15px;
display: block;
}
.content-section h2 {
color: #2c3e50;
border-bottom: 2px solid #28a745;
padding-bottom: 10px;
margin-top: 40px;
}
.content-section h3 {
color: #495057;
margin-top: 25px;
}
.formula-box {
background: #e8f5e9;
border-left: 4px solid #28a745;
padding: 15px;
margin: 15px 0;
font-family: monospace;
}
function calculateROI() {
// 1. Get input values
var initial = parseFloat(document.getElementById('inv_initial').value);
var finalVal = parseFloat(document.getElementById('inv_final').value);
var dividends = parseFloat(document.getElementById('inv_dividends').value);
var years = parseFloat(document.getElementById('inv_years').value);
// 2. Validate inputs
if (isNaN(initial) || isNaN(finalVal) || initial <= 0) {
alert("Please enter valid positive numbers for Initial Investment and Ending Value.");
return;
}
if (isNaN(dividends)) { dividends = 0; }
if (isNaN(years) || years <= 0) { years = 1; } // Default to 1 year if missing to avoid division by zero
// 3. Calculation Logic
// Net Profit = (Ending Value + Dividends) – Initial Investment
var netProfit = (finalVal + dividends) – initial;
// Simple ROI = (Net Profit / Initial Investment) * 100
var roiPercent = (netProfit / initial) * 100;
// Annualized Return (CAGR)
// Formula: ((Final Value + Dividends) / Initial Investment) ^ (1 / Years) – 1
var totalValue = finalVal + dividends;
var cagrDecimal = Math.pow((totalValue / initial), (1 / years)) – 1;
var cagrPercent = cagrDecimal * 100;
// 4. Update Results Display
document.getElementById('res_profit').innerHTML = "$" + netProfit.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,');
document.getElementById('res_roi').innerHTML = roiPercent.toFixed(2) + "%";
document.getElementById('res_cagr').innerHTML = cagrPercent.toFixed(2) + "%";
// 5. Generate Dynamic Excel Formula
// Excel Formula logic: =((Final + Dividends – Initial) / Initial)
// We will show values so they can just paste it, or references.
// Let's provide a generic formula using the numbers provided so they can verify.
var excelString = "=(" + finalVal + " + " + dividends + " – " + initial + ") / " + initial;
document.getElementById('excel_formula_display').innerHTML = excelString;
// Show results container
document.getElementById('roi_results').style.display = 'block';
}
How to Calculate Rate of Return on Investment in Excel
Calculating your Rate of Return (ROI) is essential for evaluating the efficiency of an investment or comparing the efficiency of several different investments. While the calculator above provides instant answers, knowing how to perform these calculations manually in Excel is a vital skill for financial analysis.
1. The Basic ROI Formula in Excel
The simplest way to calculate ROI is by taking the gain from the investment minus the cost of the investment, and dividing that by the cost of the investment.
The Math: ROI = (Net Profit / Cost of Investment) * 100
In Excel: Assuming your Initial Investment is in cell A2 and your Final Value is in cell B2, the formula is:
=(B2 – A2) / A2
Once you enter this formula, ensure you format the cell as a "Percentage" by clicking the % button in the Excel Home ribbon.
2. Including Dividends or Additional Income
If your investment generated cash flow (like stock dividends or rental income) during the holding period, you must add this to your final value to get an accurate return.
In Excel: Assuming Dividends are in cell C2:
=((B2 + C2) – A2) / A2
3. Calculating Annualized Return (CAGR) in Excel
If you held an investment for multiple years, a simple ROI calculation can be misleading. A 20% return over 1 year is great, but a 20% return over 10 years is poor. To standardize this, we use the Compound Annual Growth Rate (CAGR).
You can use the native Excel function RRI or write the formula manually.
Method A: Using the RRI Function
Excel has a built-in function specifically for this:
=RRI(Number_of_Years, Initial_Value, Final_Value)
Example: =RRI(5, 1000, 1500) calculates the annual growth rate required to turn $1,000 into $1,500 over 5 years.
Method B: Manual Power Formula
If you prefer the manual mathematical approach in Excel, the formula is:
=((Final_Value / Initial_Value)^(1 / Years)) – 1
This formula divides the final value by the starting value, raises the result to the power of one divided by the number of years, and subtracts one to get the decimal percentage.
4. Using XIRR for Irregular Cash Flows
If you made multiple deposits or withdrawals at different times, simple formulas won't work. You must use the XIRR function.
To use XIRR:
- Column A: Dates of transactions.
- Column B: Amounts (Negative for money out, Positive for money in/current value).
- Formula:
=XIRR(B2:B10, A2:A10)
Why is my Excel calculation different from the calculator?
Common discrepancies usually arise from:
- Time Period: Ensure you are using the exact number of years (e.g., 18 months = 1.5 years).
- Dividends: Forgetting to include reinvested dividends or cash payouts decreases your calculated return.
- Formatting: Excel may display "0.15" for 15%. Make sure to format cells as percentages to read them easily.