This calculator helps you convert an annual rate into its equivalent monthly rate. This is useful in various financial contexts where rates are quoted annually but payments or accruals occur monthly.
Monthly Rate:
function calculateMonthlyRate() {
var annualRateInput = document.getElementById("annualRate");
var monthlyRateResultElement = document.getElementById("monthlyRateResult");
// Clear previous results
monthlyRateResultElement.textContent = "";
var annualRate = parseFloat(annualRateInput.value);
// Input validation
if (isNaN(annualRate)) {
monthlyRateResultElement.textContent = "Please enter a valid number for the annual rate.";
return;
}
// The formula to convert an annual rate (r_annual) to a monthly rate (r_monthly) is:
// (1 + r_monthly)^12 = (1 + r_annual)
// So, r_monthly = (1 + r_annual)^(1/12) – 1
var monthlyRate = Math.pow(1 + annualRate, 1/12) – 1;
// Display the result, formatted as a percentage
if (!isNaN(monthlyRate)) {
monthlyRateResultElement.textContent = (monthlyRate * 100).toFixed(4) + "%";
} else {
monthlyRateResultElement.textContent = "Calculation resulted in an invalid number.";
}
}
#annualToMonthlyRateCalculator {
font-family: sans-serif;
border: 1px solid #ccc;
padding: 20px;
border-radius: 5px;
max-width: 400px;
margin: 20px auto;
background-color: #f9f9f9;
}
.calculator-inputs {
margin-bottom: 20px;
}
.input-group {
margin-bottom: 15px;
}
.input-group label {
display: block;
margin-bottom: 5px;
font-weight: bold;
}
.input-group input[type="number"] {
width: calc(100% – 12px);
padding: 8px;
border: 1px solid #ccc;
border-radius: 3px;
}
button {
background-color: #007bff;
color: white;
padding: 10px 15px;
border: none;
border-radius: 3px;
cursor: pointer;
font-size: 16px;
margin-bottom: 20px;
}
button:hover {
background-color: #0056b3;
}
#result {
margin-top: 20px;
padding-top: 15px;
border-top: 1px solid #eee;
}
#result h3 {
margin-top: 0;
color: #333;
}
#monthlyRateResult {
font-size: 1.2em;
font-weight: bold;
color: #28a745;
}