Investment Calculator with Tax Rate

.lease-calc-container {
font-family: -apple-system, BlinkMacSystemFont, “Segoe UI”, Roboto, Helvetica, Arial, sans-serif;
max-width: 800px;
margin: 20px auto;
padding: 25px;
border: 1px solid #e1e1e1;
border-radius: 12px;
background-color: #ffffff;
box-shadow: 0 4px 6px rgba(0,0,0,0.05);
color: #333;
}
.lease-calc-header {
text-align: center;
margin-bottom: 30px;
}
.lease-calc-grid {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
margin-bottom: 25px;
}
@media (max-width: 600px) {
.lease-calc-grid { grid-template-columns: 1fr; }
}
.lease-input-group {
display: flex;
flex-direction: column;
}
.lease-input-group label {
font-weight: 600;
margin-bottom: 8px;
font-size: 14px;
color: #444;
}
.lease-input-group input {
padding: 12px;
border: 1px solid #ccc;
border-radius: 6px;
font-size: 16px;
}
.lease-calc-btn {
background-color: #0056b3;
color: white;
border: none;
padding: 15px 30px;
font-size: 18px;
font-weight: bold;
border-radius: 6px;
cursor: pointer;
width: 100%;
transition: background-color 0.2s;
}
.lease-calc-btn:hover {
background-color: #004494;
}
.lease-result-box {
margin-top: 30px;
padding: 20px;
background-color: #f8f9fa;
border-radius: 8px;
border-left: 5px solid #0056b3;
display: none;
}
.lease-result-row {
display: flex;
justify-content: space-between;
margin-bottom: 10px;
font-size: 16px;
}
.lease-result-total {
font-size: 24px;
font-weight: 800;
color: #0056b3;
border-top: 1px solid #ddd;
padding-top: 10px;
margin-top: 10px;
}
.lease-content {
margin-top: 40px;
line-height: 1.6;
}
.lease-content h2 {
color: #222;
margin-top: 25px;
}
.lease-content ul {
padding-left: 20px;
}

Estimate your monthly car lease payments by entering the vehicle details below.

How Car Lease Payments are Calculated

Unlike a traditional car loan where you pay for the entire value of the vehicle, a lease payment is primarily based on the vehicle’s depreciation during the time you drive it. To understand your monthly payment, you need to look at three main components:

• Depreciation Fee: This is the value the car loses over the lease term. It is calculated as: (Adjusted Capitalized Cost – Residual Value) ÷ Term Months.
• Rent Charge (Money Factor): This is essentially the interest you pay for the leasing company’s money. It is calculated as: (Adjusted Capitalized Cost + Residual Value) × Money Factor.
• Taxes: Most states apply sales tax to the monthly payment rather than the total price of the car.

Key Leasing Terms You Should Know

Gross Capitalized Cost

This is the starting price of the vehicle used for the lease. It includes the negotiated price of the car plus any added fees, service contracts, or prior lease balances you are rolling into the new deal.

Residual Value

The residual value is the estimated worth of the car at the end of the lease term. This is set by the leasing company (the captive finance arm of the manufacturer) and is non-negotiable. A higher residual value usually results in a lower monthly payment because you are paying for less depreciation.

Money Factor

The Money Factor represents the interest rate on a lease. It is often written as a small decimal (e.g., 0.00125). To convert a Money Factor into a standard APR, multiply it by 2400. Conversely, to find the Money Factor from an APR, divide the APR by 2400.

Example Calculation

Imagine you lease a car with a negotiated price of $30,000. You put $2,000 down. The 36-month residual is 60% ($18,000). The Money Factor is 0.0015 (3.6% APR).

• Depreciation: ($28,000 – $18,000) / 36 = $277.77
• Rent Charge: ($28,000 + $18,000) * 0.0015 = $69.00
• Base Payment: $277.77 + $69.00 = $346.77 (plus taxes)

function calculateLease() {
var msrp = parseFloat(document.getElementById(‘msrp’).value);
var negotiatedPrice = parseFloat(document.getElementById(‘negotiatedPrice’).value);
var downPayment = parseFloat(document.getElementById(‘downPayment’).value) || 0;
var tradeIn = parseFloat(document.getElementById(‘tradeIn’).value) || 0;
var term = parseFloat(document.getElementById(‘leaseTerm’).value);
var resPercent = parseFloat(document.getElementById(‘residualPercentage’).value);
var interestInput = parseFloat(document.getElementById(‘interestRate’).value);
var taxRate = parseFloat(document.getElementById(‘taxRate’).value) || 0;
if (isNaN(msrp) || isNaN(negotiatedPrice) || isNaN(term) || term <= 0) {
alert("Please enter valid numeric values for MSRP, Price, and Term.");
return;
}
// 1. Calculate Capitalized Cost
var capCost = negotiatedPrice – downPayment – tradeIn;
// 2. Calculate Residual Value
var residualValue = msrp * (resPercent / 100);
// 3. Determine Money Factor
var moneyFactor = 0;
if (interestInput < 0.2) {
// Assume user entered Money Factor decimal
moneyFactor = interestInput;
} else {
// Assume user entered APR percentage
moneyFactor = interestInput / 2400;
}
// 4. Monthly Depreciation
var monthlyDepreciation = (capCost – residualValue) / term;
if (monthlyDepreciation < 0) monthlyDepreciation = 0;
// 5. Monthly Rent Charge
var monthlyRent = (capCost + residualValue) * moneyFactor;
// 6. Subtotal and Tax
var basePayment = monthlyDepreciation + monthlyRent;
var taxAmount = basePayment * (taxRate / 100);
var totalMonthly = basePayment + taxAmount;
// Display Results
document.getElementById('resGrossCap').innerText = "$" + capCost.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById('resResidual').innerText = "$" + residualValue.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById('resDepreciation').innerText = "$" + monthlyDepreciation.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById('resRent').innerText = "$" + monthlyRent.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById('resTotal').innerText = "$" + totalMonthly.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
document.getElementById('leaseResult').style.display = 'block';
}