.calc-container {
max-width: 800px;
margin: 0 auto;
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
color: #333;
line-height: 1.6;
}
.calc-box {
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;
color: #2c3e50;
margin-bottom: 25px;
font-size: 28px;
font-weight: 700;
}
.input-grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
}
@media (max-width: 600px) {
.input-grid {
grid-template-columns: 1fr;
}
}
.input-group {
margin-bottom: 15px;
}
.input-group label {
display: block;
margin-bottom: 8px;
font-weight: 600;
font-size: 14px;
color: #555;
}
.input-group input {
width: 100%;
padding: 12px;
border: 1px solid #ced4da;
border-radius: 4px;
font-size: 16px;
box-sizing: border-box;
transition: border-color 0.2s;
}
.input-group input:focus {
border-color: #007bff;
outline: none;
}
.calc-btn {
width: 100%;
padding: 15px;
background-color: #28a745;
color: white;
border: none;
border-radius: 4px;
font-size: 18px;
font-weight: bold;
cursor: pointer;
margin-top: 10px;
transition: background-color 0.2s;
}
.calc-btn:hover {
background-color: #218838;
}
.result-section {
margin-top: 30px;
padding-top: 20px;
border-top: 2px solid #e9ecef;
display: none;
}
.result-card {
background: #fff;
padding: 20px;
border-radius: 6px;
border: 1px solid #dee2e6;
text-align: center;
margin-bottom: 15px;
}
.result-label {
font-size: 14px;
text-transform: uppercase;
letter-spacing: 1px;
color: #6c757d;
margin-bottom: 5px;
}
.result-value {
font-size: 32px;
font-weight: 800;
color: #28a745;
}
.result-sub {
font-size: 14px;
color: #6c757d;
margin-top: 5px;
}
.calc-article h2 {
color: #2c3e50;
margin-top: 30px;
font-size: 24px;
}
.calc-article h3 {
color: #34495e;
font-size: 20px;
margin-top: 25px;
}
.calc-article p {
margin-bottom: 15px;
font-size: 17px;
}
.calc-article ul {
margin-bottom: 20px;
padding-left: 20px;
}
.calc-article li {
margin-bottom: 10px;
}
.error-msg {
color: #dc3545;
font-size: 14px;
margin-top: 5px;
display: none;
}
function calculateRetirement() {
// Get Inputs
var currentAge = parseFloat(document.getElementById('currentAge').value);
var retireAge = parseFloat(document.getElementById('retireAge').value);
var currentSavings = parseFloat(document.getElementById('currentSavings').value);
var monthlyContrib = parseFloat(document.getElementById('monthlyContrib').value);
var annualReturn = parseFloat(document.getElementById('annualReturn').value);
var errorDiv = document.getElementById('errorDisplay');
var resultDiv = document.getElementById('resultSection');
// Validation
if (isNaN(currentAge) || isNaN(retireAge) || isNaN(currentSavings) ||
isNaN(monthlyContrib) || isNaN(annualReturn)) {
errorDiv.style.display = 'block';
resultDiv.style.display = 'none';
return;
}
if (currentAge >= retireAge) {
errorDiv.innerText = "Retirement age must be greater than current age.";
errorDiv.style.display = 'block';
resultDiv.style.display = 'none';
return;
}
errorDiv.style.display = 'none';
// Calculation Logic
// We calculate using monthly compounding to align with monthly contributions
var yearsToGrow = retireAge – currentAge;
var monthsToGrow = yearsToGrow * 12;
var monthlyRate = (annualReturn / 100) / 12;
var futureValueSavings = 0;
var futureValueContrib = 0;
// FV of Initial Savings: P * (1 + r)^n
futureValueSavings = currentSavings * Math.pow(1 + monthlyRate, monthsToGrow);
// FV of Series (Monthly Contributions): PMT * [ ((1 + r)^n – 1) / r ]
if (monthlyRate > 0) {
futureValueContrib = monthlyContrib * (Math.pow(1 + monthlyRate, monthsToGrow) – 1) / monthlyRate;
} else {
futureValueContrib = monthlyContrib * monthsToGrow;
}
var totalBalance = futureValueSavings + futureValueContrib;
// Total Principal Calculation
var totalDirectContributions = currentSavings + (monthlyContrib * monthsToGrow);
var totalInterestEarned = totalBalance – totalDirectContributions;
// 4% Rule for Income
var annualIncome = totalBalance * 0.04;
var monthlyIncome = annualIncome / 12;
// Formatting Function
var currencyFormat = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
maximumFractionDigits: 0
});
// Update DOM
document.getElementById('totalSavings').innerText = currencyFormat.format(totalBalance);
document.getElementById('totalPrincipal').innerText = currencyFormat.format(totalDirectContributions);
document.getElementById('totalInterest').innerText = currencyFormat.format(totalInterestEarned);
document.getElementById('monthlyIncome').innerText = currencyFormat.format(monthlyIncome);
resultDiv.style.display = 'block';
}
Retirement Savings Calculator
Please fill out all fields with valid numbers.
Total Savings at Retirement
$0
Total accumulated balance
Total Contributions
$0
Interest Earned
$0
Est. Monthly Retirement Income
$0
Based on the 4% Safe Withdrawal Rule
How to Plan for Your Financial Freedom
Planning for retirement is one of the most critical financial tasks you will undertake. Using a Retirement Savings Calculator allows you to visualize how your current savings habits translate into future security. The earlier you start, the more you can leverage the power of compound interest to build a substantial nest egg.
Understanding the Calculation
This calculator projects your future wealth based on five key variables:
- Current Age & Retirement Age: These determine your "time horizon"—the number of years your money has to grow. A longer time horizon exponentially increases your potential returns.
- Current Savings: The starting principal that will begin compounding immediately.
- Monthly Contribution: The amount you add to your investment accounts (401k, IRA, Brokerage) every month. Consistency here is key.
- Expected Annual Return: The average percentage your investments grow each year. Historically, the stock market (S&P 500) has returned about 10% annually before inflation, though conservative estimates often use 6-8%.
The Power of Compound Interest
Einstein famously called compound interest the "eighth wonder of the world." It works by earning interest not just on your initial savings, but also on the interest you've already earned. In our calculator, you will see a breakdown of Total Contributions (money you put in) versus Interest Earned (money your money made). Over long periods (20+ years), the interest earned often exceeds the total contributions significantly.
What is the "Safe Withdrawal Rate"?
The estimated monthly income result in this tool is based on the 4% Rule. This financial rule of thumb suggests that you can withdraw 4% of your total portfolio value in the first year of retirement, and adjust that amount for inflation in subsequent years, with a high probability of not running out of money for 30 years.
How to Improve Your Results
If the projected numbers look lower than you hoped, consider these strategies:
- Increase Contributions: Even an extra $50 a month can make a difference of tens of thousands of dollars over 30 years.
- Delay Retirement: Working just 2-3 years longer gives your portfolio more time to compound and reduces the number of years you need to draw from it.
- Review Your Fees: ensure your investment management fees are low, as high fees eat directly into your annual return.