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-wrapper {
background: #f8f9fa;
border: 1px solid #e9ecef;
border-radius: 8px;
padding: 30px;
box-shadow: 0 4px 6px rgba(0,0,0,0.05);
margin-bottom: 40px;
}
.calc-title {
text-align: center;
margin-bottom: 25px;
color: #2c3e50;
font-size: 24px;
font-weight: 700;
}
.input-group {
margin-bottom: 20px;
}
.input-group label {
display: block;
margin-bottom: 8px;
font-weight: 600;
color: #495057;
}
.input-wrapper {
position: relative;
}
.input-prefix {
position: absolute;
left: 12px;
top: 50%;
transform: translateY(-50%);
color: #6c757d;
font-weight: bold;
}
.input-suffix {
position: absolute;
right: 12px;
top: 50%;
transform: translateY(-50%);
color: #6c757d;
font-weight: bold;
}
input[type="number"] {
width: 100%;
padding: 12px 12px 12px 35px; /* space for prefix */
border: 1px solid #ced4da;
border-radius: 6px;
font-size: 16px;
box-sizing: border-box;
transition: border-color 0.15s ease-in-out;
}
input[type="number"]:focus {
border-color: #2ecc71;
outline: 0;
box-shadow: 0 0 0 0.2rem rgba(46, 204, 113, 0.25);
}
.calc-btn {
width: 100%;
background-color: #2ecc71;
color: white;
border: none;
padding: 15px;
font-size: 18px;
font-weight: 600;
border-radius: 6px;
cursor: pointer;
transition: background-color 0.2s;
margin-top: 10px;
}
.calc-btn:hover {
background-color: #27ae60;
}
.results-container {
margin-top: 25px;
padding: 20px;
background-color: #fff;
border-radius: 6px;
border-left: 5px solid #2ecc71;
display: none;
}
.result-row {
display: flex;
justify-content: space-between;
margin-bottom: 12px;
padding-bottom: 12px;
border-bottom: 1px solid #f1f1f1;
}
.result-row:last-child {
border-bottom: none;
margin-bottom: 0;
padding-bottom: 0;
}
.result-label {
font-weight: 600;
color: #555;
}
.result-value {
font-weight: 700;
font-size: 18px;
color: #2c3e50;
}
.positive {
color: #2ecc71;
}
.negative {
color: #e74c3c;
}
.article-section {
margin-top: 50px;
border-top: 1px solid #eee;
padding-top: 30px;
}
.article-section h2 {
color: #2c3e50;
font-size: 24px;
margin-top: 30px;
}
.article-section h3 {
color: #34495e;
font-size: 20px;
margin-top: 25px;
}
.article-section p {
margin-bottom: 15px;
font-size: 16px;
color: #4a4a4a;
}
.article-section ul {
margin-bottom: 20px;
padding-left: 20px;
}
.article-section li {
margin-bottom: 10px;
}
.formula-box {
background: #f8f9fa;
padding: 15px;
border-radius: 4px;
font-family: monospace;
margin: 20px 0;
border: 1px solid #ddd;
}
@media (max-width: 600px) {
.calculator-wrapper {
padding: 20px;
}
}
function calculateRateOfReturn() {
// 1. Get input values
var initial = parseFloat(document.getElementById('initialVal').value);
var final = parseFloat(document.getElementById('finalVal').value);
var income = parseFloat(document.getElementById('incomeVal').value);
var years = parseFloat(document.getElementById('periodVal').value);
// Handle empty or NaN inputs
if (isNaN(income)) income = 0;
var resultsContainer = document.getElementById('resultContainer');
var cagrRow = document.getElementById('cagrRow');
// Validation
if (isNaN(initial) || isNaN(final) || initial 0
var cagr = 0;
var hasCAGR = false;
if (!isNaN(years) && years > 0) {
// Formula: ( (Ending Value + Income) / Beginning Value ) ^ (1/n) – 1
// Note: If totalFinalValue is negative, CAGR is complex, here we assume standard positive value flows or handle basic math
if (totalFinalValue >= 0) {
cagr = (Math.pow(totalFinalValue / initial, 1 / years) – 1) * 100;
hasCAGR = true;
}
}
// 5. Update HTML Output
var netProfitElem = document.getElementById('resultNetProfit');
var rorElem = document.getElementById('resultRoR');
var cagrElem = document.getElementById('resultCAGR');
// Format Currency
netProfitElem.innerHTML = (netProfit = 0 ? "positive" : "negative");
// Format Percentages
rorElem.innerHTML = rorPercentage.toFixed(2) + "%";
rorElem.className = "result-value " + (rorPercentage >= 0 ? "positive" : "negative");
if (hasCAGR) {
cagrRow.style.display = 'flex';
cagrElem.innerHTML = cagr.toFixed(2) + "%";
cagrElem.className = "result-value " + (cagr >= 0 ? "positive" : "negative");
} else {
cagrRow.style.display = 'none';
}
// Show results
resultsContainer.style.display = 'block';
}
How to Calculate Rate of Return Percentage
Understanding how to calculate your rate of return (RoR) is fundamental to evaluating the success of any investment. Whether you are analyzing a stock portfolio, a real estate property, or a small business investment, the RoR percentage tells you exactly how much your money has grown (or shrunk) relative to your initial contribution.
The calculator above helps you determine both your simple return and your annualized return (CAGR), taking into account capital appreciation and income generated (such as dividends or interest).
The Rate of Return Formula
The basic formula for calculating the percentage rate of return is straightforward. It measures the net gain or loss of an investment over a specified period, expressed as a percentage of the investment's initial cost.
Rate of Return (%) = [(Current Value + Distributions – Initial Value) / Initial Value] × 100
Where:
- Current Value: The value of the investment today or the price at which you sold it.
- Distributions: Any cash flow received during the holding period (dividends, interest payments, or rent).
- Initial Value: The original purchase price or amount invested.
Step-by-Step Calculation Example
Let's look at a practical example to clarify the process. Suppose you purchased a stock for $1,000.
- Determine Initial Value: You invested $1,000.
- Determine Ending Value: Three years later, the stock is worth $1,200.
- Add Income: During those three years, you received $50 in dividends.
- Calculate Net Profit: ($1,200 + $50) – $1,000 = $250 Profit.
- Calculate Percentage: ($250 / $1,000) × 100 = 25%.
In this scenario, your total Rate of Return is 25%.
Simple Return vs. Annualized Return (CAGR)
While the simple rate of return gives you the total percentage gain, it does not account for the time period. A 25% return over 1 year is excellent, but a 25% return over 10 years is poor.
To compare investments held for different periods, investors use the Compound Annual Growth Rate (CAGR). This metric smooths out the return to show what the annual growth rate would have been if the investment had grown at a steady rate.
CAGR = [(Ending Value / Beginning Value) ^ (1 / Number of Years)] – 1
Using the example above over a 3-year period:
- Total Value ($1,250) divided by Initial Value ($1,000) = 1.25
- Raise 1.25 to the power of (1/3) ≈ 1.0772
- Subtract 1 and multiply by 100 ≈ 7.72%
This means your investment effectively grew by 7.72% every year for three years.
Why Include Distributions?
Many novice investors make the mistake of calculating return based solely on price appreciation. However, for assets like dividend-paying stocks, bonds, or rental properties, income distributions can make up a significant portion of the total return. Failing to include these payments will underestimate your actual performance.