body {
font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
background-color: #f8f9fa;
color: #333;
line-height: 1.6;
margin: 0;
padding: 20px;
}
.roi-calc-container {
max-width: 700px;
margin: 30px auto;
background-color: #ffffff;
padding: 30px;
border-radius: 8px;
box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}
h1, h2 {
color: #004a99;
text-align: center;
margin-bottom: 20px;
}
.input-group {
margin-bottom: 20px;
display: flex;
flex-direction: column;
}
.input-group label {
display: block;
margin-bottom: 8px;
font-weight: bold;
color: #004a99;
}
.input-group input[type="number"] {
padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
font-size: 1rem;
transition: border-color 0.3s ease;
}
.input-group input[type="number"]:focus {
border-color: #004a99;
outline: none;
}
button {
background-color: #28a745;
color: white;
border: none;
padding: 12px 20px;
border-radius: 4px;
font-size: 1.1rem;
cursor: pointer;
transition: background-color 0.3s ease;
width: 100%;
margin-top: 10px;
}
button:hover {
background-color: #218838;
}
#result {
margin-top: 30px;
padding: 20px;
background-color: #e9ecef;
border-left: 5px solid #004a99;
border-radius: 4px;
}
#result p {
margin: 0;
font-size: 1.2rem;
font-weight: bold;
text-align: center;
color: #004a99;
}
.article-content {
margin-top: 40px;
padding-top: 30px;
border-top: 1px solid #eee;
}
.article-content h3 {
color: #004a99;
margin-bottom: 15px;
}
.article-content p, .article-content ul {
margin-bottom: 15px;
}
.article-content li {
margin-bottom: 8px;
}
@media (max-width: 600px) {
.roi-calc-container {
padding: 20px;
}
button {
font-size: 1rem;
padding: 10px 15px;
}
#result p {
font-size: 1.1rem;
}
}
Understanding Investment Return on Investment (ROI)
The Return on Investment (ROI) is a performance measure used to evaluate the efficiency and profitability of an investment. It is expressed as a percentage and helps investors compare the profitability of different investments. A positive ROI indicates that the investment has generated profit, while a negative ROI signifies a loss.
How ROI is Calculated
The fundamental formula for ROI is:
ROI = [(Current Value of Investment – Cost of Investment) / Cost of Investment] * 100
However, in a more comprehensive scenario, especially for investments held over time, we need to account for additional capital contributions (like further investments) and capital withdrawn. The formula adjusted for these factors is:
Net Profit = (Current Value + Total Withdrawals) – (Initial Investment + Additional Investment)
Total Investment Cost = Initial Investment + Additional Investment
ROI = (Net Profit / Total Investment Cost) * 100
In our calculator:
- Initial Investment ($): The principal amount initially put into the investment.
- Current Value ($): The present market value of the investment.
- Additional Investment ($): Any further capital injected into the investment over its lifetime.
- Total Withdrawals ($): The sum of all money taken out from the investment.
By using these inputs, the calculator provides a more accurate picture of your investment's performance by considering all cash flows.
Why ROI is Important
- Performance Measurement: It directly quantifies how much money an investment has made or lost relative to its cost.
- Comparison Tool: Allows for easy comparison between different investment opportunities, regardless of their size.
- Decision Making: Helps investors decide whether to continue an investment, sell it, or allocate more capital.
- Profitability Indicator: A simple yet powerful metric to gauge the success of any financial venture.
Example Scenario
Let's say you made an Initial Investment of $10,000 into a stock. Over time, you added another $1,000 as Additional Investment. You also withdrew $500 from the investment. The stock has grown, and its Current Value is now $13,500.
Using the calculator inputs:
- Initial Investment: $10,000
- Current Value: $13,500
- Additional Investment: $1,000
- Total Withdrawals: $500
Calculation Breakdown:
- Net Profit = ($13,500 + $500) – ($10,000 + $1,000) = $14,000 – $11,000 = $3,000
- Total Investment Cost = $10,000 + $1,000 = $11,000
- ROI = ($3,000 / $11,000) * 100 = 27.27%
This means your investment has yielded a 27.27% return relative to the total capital you've put into it.
function calculateROI() {
var initialInvestment = parseFloat(document.getElementById("initialInvestment").value);
var currentValue = parseFloat(document.getElementById("currentValue").value);
var additionalInvestment = parseFloat(document.getElementById("additionalInvestment").value);
var totalWithdrawals = parseFloat(document.getElementById("totalWithdrawals").value);
var resultDiv = document.getElementById("result");
// Check if inputs are valid numbers
if (isNaN(initialInvestment) || isNaN(currentValue) || isNaN(additionalInvestment) || isNaN(totalWithdrawals)) {
resultDiv.innerHTML = "Please enter valid numbers for all fields.";
return;
}
// Ensure costs are not negative, and values/withdrawals are not negative
if (initialInvestment < 0 || additionalInvestment < 0 || currentValue < 0 || totalWithdrawals 0) {
roi = Infinity; // Infinitely good if profit with zero cost
} else if (netProfit = 0) {
resultText = "Your Investment ROI: " + roi.toFixed(2) + "%";
} else {
resultText = "Your Investment ROI: " + roi.toFixed(2) + "%";
}
resultDiv.innerHTML = "" + resultText + "";
}