Planning for retirement is a crucial step in securing your financial future. This calculator helps you estimate how much you need to save to achieve your desired retirement income.
.calculator-container {
font-family: sans-serif;
max-width: 600px;
margin: 20px auto;
padding: 20px;
border: 1px solid #ddd;
border-radius: 8px;
box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}
.calculator-container h2 {
text-align: center;
margin-bottom: 15px;
color: #333;
}
.calculator-container p {
text-align: center;
margin-bottom: 25px;
color: #555;
font-size: 0.95em;
}
.calculator-inputs {
display: grid;
grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
gap: 15px;
margin-bottom: 20px;
}
.input-group {
display: flex;
flex-direction: column;
}
.input-group label {
margin-bottom: 5px;
font-weight: bold;
color: #444;
}
.input-group input {
padding: 10px;
border: 1px solid #ccc;
border-radius: 4px;
font-size: 1em;
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.calculator-container button {
display: block;
width: 100%;
padding: 12px 20px;
background-color: #007bff;
color: white;
border: none;
border-radius: 4px;
font-size: 1.1em;
cursor: pointer;
transition: background-color 0.3s ease;
}
.calculator-container button:hover {
background-color: #0056b3;
}
.calculator-result {
margin-top: 25px;
padding: 15px;
background-color: #e9ecef;
border-radius: 4px;
text-align: center;
font-size: 1.1em;
color: #333;
font-weight: bold;
}
function calculateRetirementGoal() {
var currentAge = parseFloat(document.getElementById("currentAge").value);
var retirementAge = parseFloat(document.getElementById("retirementAge").value);
var currentSavings = parseFloat(document.getElementById("currentSavings").value);
var annualIncome = parseFloat(document.getElementById("annualIncome").value);
var retirementIncomePercentage = parseFloat(document.getElementById("retirementIncomePercentage").value) / 100;
var annualReturnRate = parseFloat(document.getElementById("annualReturnRate").value) / 100;
var inflationRate = parseFloat(document.getElementById("inflationRate").value) / 100;
var retirementDuration = parseFloat(document.getElementById("retirementDuration").value);
var resultDiv = document.getElementById("retirementResult");
if (isNaN(currentAge) || isNaN(retirementAge) || isNaN(currentSavings) || isNaN(annualIncome) || isNaN(retirementIncomePercentage) || isNaN(annualReturnRate) || isNaN(inflationRate) || isNaN(retirementDuration)) {
resultDiv.innerHTML = "Please enter valid numbers for all fields.";
return;
}
if (retirementAge <= currentAge) {
resultDiv.innerHTML = "Your retirement age must be greater than your current age.";
return;
}
var yearsToRetirement = retirementAge – currentAge;
var desiredAnnualRetirementIncomeNominal = annualIncome * retirementIncomePercentage;
// Calculate future value of desired annual income considering inflation
var desiredAnnualRetirementIncomeFuture = desiredAnnualRetirementIncomeNominal * Math.pow(1 + inflationRate, yearsToRetirement);
// Calculate total retirement nest egg needed using the withdrawal rate (simplified approach assuming a fixed withdrawal rate to sustain income for duration)
// A common rule of thumb is the 4% rule, but we can adapt it or use a formula that accounts for duration and investment returns during retirement.
// For simplicity, let's estimate the required lump sum to generate the desired income for the duration, considering investment returns during retirement.
// This is a complex calculation and can be simplified. A more robust calculation would use annuities or present value of a growing annuity.
// Simplified approach: Calculate the present value of an annuity with payments growing at inflation rate.
// PV = P * [1 – ((1+r)/(1+i))^n] / (i-r)
// Where P = first payment (desiredAnnualRetirementIncomeFuture), r = investment return rate, i = inflation rate, n = retirement duration.
var totalRetirementNestEgg;
if (annualReturnRate === inflationRate) {
totalRetirementNestEgg = desiredAnnualRetirementIncomeFuture * retirementDuration;
} else {
totalRetirementNestEgg = desiredAnnualRetirementIncomeFuture * (1 – Math.pow((1 + annualReturnRate) / (1 + inflationRate), retirementDuration)) / (inflationRate – annualReturnRate);
}
// Ensure we don't have a negative nest egg if rates are very unusual or duration is short
if (totalRetirementNestEgg < 0) {
totalRetirementNestEgg = 0;
}
// Calculate the future value of current savings
var futureValueCurrentSavings = currentSavings * Math.pow(1 + annualReturnRate, yearsToRetirement);
// Calculate the shortfall
var savingsShortfall = totalRetirementNestEgg – futureValueCurrentSavings;
// Calculate how much needs to be saved annually to meet the shortfall
// This uses the future value of an ordinary annuity formula: FV = P * [((1 + r)^n – 1) / r]
// Solving for P (annual savings): P = FV * r / ((1 + r)^n – 1)
var requiredAnnualSavings;
if (yearsToRetirement === 0) {
requiredAnnualSavings = Math.max(0, savingsShortfall); // If retiring now, need the whole shortfall
} else if (annualReturnRate === 0) {
requiredAnnualSavings = savingsShortfall / yearsToRetirement; // Simple average if no return
}
else {
requiredAnnualSavings = savingsShortfall * annualReturnRate / (Math.pow(1 + annualReturnRate, yearsToRetirement) – 1);
}
// Ensure required annual savings is not negative
requiredAnnualSavings = Math.max(0, requiredAnnualSavings);
var formattedTotalNestEgg = totalRetirementNestEgg.toLocaleString('en-US', { style: 'currency', currency: 'USD' });
var formattedFutureCurrentSavings = futureValueCurrentSavings.toLocaleString('en-US', { style: 'currency', currency: 'USD' });
var formattedShortfall = savingsShortfall.toLocaleString('en-US', { style: 'currency', currency: 'USD' });
var formattedAnnualSavings = requiredAnnualSavings.toLocaleString('en-US', { style: 'currency', currency: 'USD' });
resultDiv.innerHTML =
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