Kbb Auto Loan Calculator

KBB Auto Loan Calculator – Estimate Your Monthly Payments :root { –primary-color: #004a99; –success-color: #28a745; –background-color: #f8f9fa; –text-color: #333; –white-color: #fff; –border-color: #ddd; –shadow-color: rgba(0, 0, 0, 0.1); } body { font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; background-color: var(–background-color); color: var(–text-color); margin: 0; padding: 0; line-height: 1.6; } .container { max-width: 1000px; margin: 20px auto; padding: 20px; background-color: var(–white-color); border-radius: 8px; box-shadow: 0 4px 15px var(–shadow-color); } header { background-color: var(–primary-color); color: var(–white-color); padding: 20px 0; text-align: center; margin-bottom: 20px; border-radius: 8px 8px 0 0; } header h1 { margin: 0; font-size: 2.2em; } .sub-header { font-size: 1.1em; margin-top: 5px; opacity: 0.9; } .calculator-section { margin-bottom: 40px; padding: 25px; background-color: var(–white-color); border: 1px solid var(–border-color); border-radius: 8px; 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KBB Auto Loan Calculator

Estimate Your Monthly Car Payments Accurately

Auto Loan Details

3 Years 4 Years 5 Years 6 Years 7 Years
e.g., 6.5 for 6.5%

Your Estimated Loan Payments

$0.00
$0.00

Total Interest

$0.00

Total Cost

$0.00

Loan Amount

Monthly Payment is calculated using the loan principal, interest rate, and loan term. Total Interest is the sum of all monthly interest payments over the loan's life. Total Cost is the sum of the loan amount and total interest.

What is a KBB Auto Loan Calculator?

{primary_keyword} is a specialized financial tool designed to help consumers estimate the monthly payments, total interest, and overall cost associated with financing a vehicle purchase. While not directly provided by Kelley Blue Book (KBB) itself, the concept often refers to using car valuation data from KBB in conjunction with loan calculation principles to arrive at a realistic estimate for an auto loan. This type of calculator is invaluable for anyone looking to buy a car, whether new or used, and needs to understand the financial commitment involved.

Anyone planning to finance a car should use this calculator. This includes first-time car buyers, individuals looking to upgrade their current vehicle, or those exploring financing options for a used car listed with a KBB value. It helps in budgeting and comparing different loan offers before committing.

A common misconception is that the calculator will provide an exact loan offer or the best possible interest rate. In reality, it's an estimation tool based on the inputs provided. Actual loan terms and rates depend on your creditworthiness, the lender, and current market conditions. Another misconception is that KBB *provides* the calculator; KBB is primarily known for vehicle valuation, and many third-party financial sites offer calculators that *incorporate* KBB data or general auto loan principles.

Key Features of a KBB Auto Loan Calculator:

  • Vehicle Price Input: Allows users to enter the anticipated price of the car.
  • Down Payment: Accounts for any upfront cash paid towards the vehicle.
  • Loan Term: Specifies the duration of the loan in years or months.
  • Interest Rate: Estimates the annual percentage rate (APR) for the loan.
  • Monthly Payment Estimation: Calculates the expected fixed monthly payment.
  • Total Interest Calculation: Shows the total amount of interest paid over the life of the loan.
  • Total Loan Cost: Displays the sum of the principal loan amount and all interest paid.

By inputting these variables, users gain a clearer picture of their financial responsibility, enabling informed decisions and better negotiation with dealerships or lenders. Understanding these figures is a crucial step in the car buying process, helping to avoid financial strain.

KBB Auto Loan Calculator Formula and Mathematical Explanation

The core of the {primary_keyword} relies on the standard formula for calculating the monthly payment of an amortizing loan. This formula, derived from the principles of present value of an annuity, helps determine a fixed payment that covers both principal and interest over the loan's life.

The Monthly Payment Formula:

The formula used to calculate the fixed monthly payment (M) is:

M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1]

Where:

  • M = Monthly Payment
  • P = Principal Loan Amount (Vehicle Price – Down Payment)
  • i = Monthly Interest Rate (Annual Interest Rate / 12 / 100)
  • n = Total Number of Payments (Loan Term in Years * 12)

Variable Explanations and Typical Ranges:

Variable Meaning Unit Typical Range
Vehicle Price The total price of the car being purchased. USD ($) $5,000 – $100,000+
Down Payment The upfront cash amount paid towards the vehicle price. USD ($) $0 – Vehicle Price
Loan Amount (P) The net amount borrowed after the down payment. Calculated as (Vehicle Price – Down Payment). USD ($) $0 – Vehicle Price
Loan Term The duration of the loan. Years 1 – 7 Years
Annual Interest Rate (APR) The yearly cost of borrowing expressed as a percentage. % 2% – 25%+ (Varies greatly by credit score and market)
Monthly Interest Rate (i) The interest rate applied each month. Calculated as (Annual Interest Rate / 100) / 12. Decimal 0.00167 – 0.0208+
Number of Payments (n) The total number of monthly payments over the loan term. Calculated as (Loan Term in Years * 12). Count 12 – 84
Monthly Payment (M) The fixed amount paid each month. USD ($) Calculated value
Total Interest Paid Sum of all interest paid over the loan term. Calculated as (M * n) – P. USD ($) Calculated value
Total Cost The sum of the principal loan amount and total interest paid. Calculated as P + Total Interest Paid. USD ($) Calculated value

Calculation Steps:

  1. Determine the Principal Loan Amount (P): Subtract the down payment from the vehicle price.
  2. Calculate the Monthly Interest Rate (i): Divide the annual interest rate by 12 and then by 100 to convert the percentage to a decimal monthly rate.
  3. Calculate the Total Number of Payments (n): Multiply the loan term in years by 12.
  4. Apply the Monthly Payment Formula: Plug P, i, and n into the annuity formula to find M.
  5. Calculate Total Interest Paid: Multiply the monthly payment (M) by the total number of payments (n) and then subtract the principal loan amount (P).
  6. Calculate Total Cost: Add the principal loan amount (P) to the Total Interest Paid.

This systematic approach ensures all components of the auto loan are accounted for, providing a comprehensive financial overview. Understanding these calculations helps in demystifying the car loan process and empowers consumers to make informed financial decisions.

Practical Examples (Real-World Use Cases)

Example 1: Buying a Popular Sedan

Sarah is looking to buy a reliable used sedan. KBB values the car at $25,000. She plans to put down $4,000 and has secured a loan offer with a 5-year term (60 months) at an 8% annual interest rate. She wants to know her estimated monthly payment.

  • Vehicle Price: $25,000
  • Down Payment: $4,000
  • Loan Term: 5 Years (60 months)
  • Annual Interest Rate: 8.0%

Calculations:

  • Loan Amount (P) = $25,000 – $4,000 = $21,000
  • Monthly Interest Rate (i) = (8.0 / 100) / 12 = 0.006667
  • Number of Payments (n) = 5 * 12 = 60

Using the loan payment formula, Sarah's estimated monthly payment (M) would be approximately $415.80.

Results:

  • Estimated Monthly Payment: $415.80
  • Total Interest Paid: ($415.80 * 60) – $21,000 = $3,948.00
  • Total Cost of Loan: $21,000 + $3,948.00 = $24,948.00

Financial Interpretation: Sarah will pay just under $4,000 in interest over five years. Knowing this, she might consider saving for a larger down payment or exploring options for a lower interest rate to reduce the overall cost of the car.

Example 2: Financing a New SUV with a Longer Term

John is purchasing a new SUV priced at $45,000. He has $8,000 for a down payment and is considering a longer loan term of 7 years (84 months) to lower his monthly payments, with an APR of 7.5%. He wants to see the impact on his finances.

  • Vehicle Price: $45,000
  • Down Payment: $8,000
  • Loan Term: 7 Years (84 months)
  • Annual Interest Rate: 7.5%

Calculations:

  • Loan Amount (P) = $45,000 – $8,000 = $37,000
  • Monthly Interest Rate (i) = (7.5 / 100) / 12 = 0.00625
  • Number of Payments (n) = 7 * 12 = 84

Using the loan payment formula, John's estimated monthly payment (M) would be approximately $517.56.

Results:

  • Estimated Monthly Payment: $517.56
  • Total Interest Paid: ($517.56 * 84) – $37,000 = $6,274.04
  • Total Cost of Loan: $37,000 + $6,274.04 = $43,274.04

Financial Interpretation: While the 7-year term results in a lower monthly payment compared to a 5-year term for a similar loan amount, John will pay significantly more in interest ($6,274.04 vs. $3,948.00 in Example 1). This highlights the trade-off between lower monthly affordability and higher long-term cost. He should weigh this carefully against his budget and how long he plans to keep the vehicle. For more insights, one might check related tools.

How to Use This KBB Auto Loan Calculator

Using the {primary_keyword} is straightforward. Follow these steps to get accurate estimations for your car financing:

Step-by-Step Instructions:

  1. Enter Vehicle Price: Input the total price of the car you intend to buy. This figure can be found on the dealership's price sticker, online listings (potentially cross-referenced with KBB's valuation tools), or your purchase agreement.
  2. Specify Down Payment: Enter the total amount of cash you plan to pay upfront. This reduces the amount you need to borrow.
  3. Select Loan Term: Choose the desired duration for your loan from the dropdown menu. Options typically range from 3 to 7 years. Longer terms mean lower monthly payments but more total interest paid.
  4. Input Annual Interest Rate (APR): Enter the Annual Percentage Rate (APR) offered by your lender or the rate you anticipate. This is a crucial factor affecting your total cost. If you don't have a specific rate, you can use an estimated average based on current market conditions or your credit score.
  5. Click "Calculate Loan": Once all fields are filled, click this button. The calculator will process the inputs using the standard auto loan formula.

How to Read the Results:

  • Estimated Monthly Payment: This is the primary result, displayed prominently. It's the amount you'll need to pay each month to cover the loan principal and interest.
  • Total Interest Paid: This shows the cumulative interest you'll pay over the entire loan term. A higher interest amount means the loan is more expensive overall.
  • Total Cost: This is the sum of the initial loan amount and all the interest paid. It represents the true cost of the vehicle when financed.
  • Loan Amount: This clarifies the principal amount borrowed after your down payment.

Decision-Making Guidance:

Use these results to make informed decisions:

  • Budgeting: Ensure the calculated monthly payment fits comfortably within your monthly budget. If it's too high, consider a less expensive vehicle, a larger down payment, a longer loan term (cautiously), or negotiating a lower interest rate.
  • Total Cost Comparison: Compare the total cost of loans with different terms or interest rates. A slightly higher monthly payment on a shorter term can save you thousands in interest over time.
  • Negotiation Power: Understanding your estimated payments and total costs can give you leverage when negotiating with dealerships or comparing loan offers from different lenders. You'll know what a fair deal looks like.
  • Credit Score Impact: If the calculated payments seem too high, it might be a sign that improving your credit score to secure a lower APR could be beneficial. Learn about improving your credit score for better loan terms.

This calculator is a powerful tool for financial planning related to car purchases. Remember to use realistic figures for the best possible outcome.

Key Factors That Affect KBB Auto Loan Results

Several factors significantly influence the outcome of your auto loan calculations and the actual loan terms you receive. Understanding these can help you optimize your financing.

  1. Credit Score:

    This is arguably the most critical factor. Lenders use your credit score to assess your risk as a borrower. A higher credit score (typically 700+) generally qualifies you for lower interest rates (APR), significantly reducing your total interest paid and monthly payments. Conversely, a lower score often results in higher APRs or even loan denial. This directly impacts the 'Annual Interest Rate' input in the calculator.

  2. Loan Term (Duration):

    The length of the loan directly affects both the monthly payment and the total interest paid. A longer term (e.g., 7 years vs. 5 years) will result in lower monthly payments, making the car seem more affordable upfront. However, you'll pay substantially more interest over the life of the loan because the principal is outstanding for a longer period. This is reflected in the 'Loan Term' input and impacts 'Total Interest Paid' and 'Total Cost'.

  3. Down Payment Amount:

    A larger down payment reduces the principal loan amount (P). This means you borrow less money, leading to lower monthly payments and significantly less interest paid over time. It also makes you a less risky borrower in the eyes of the lender, potentially helping you secure a better interest rate. This relates directly to the 'Down Payment' and 'Loan Amount' variables.

  4. Annual Interest Rate (APR):

    The APR represents the actual yearly cost of borrowing, including fees. Even a small difference in the APR can have a massive impact on your total loan cost. For instance, a 1% difference on a $30,000 loan over 5 years can amount to over $1,000 in extra interest. This is the 'Annual Interest Rate' input and is a primary driver of the monthly payment and total interest.

  5. Vehicle Price and Type:

    The higher the vehicle's price, the larger the loan amount and potentially the higher the monthly payment and total interest. Certain types of vehicles, like luxury cars or performance models, might also carry higher insurance costs, which, while not directly part of the loan calculation, add to the overall cost of ownership and affect affordability.

  6. Lender Fees and Financing Charges:

    While the standard auto loan formula doesn't always explicitly include individual fees, the APR often incorporates some lender fees. However, some loans might have origination fees, documentation fees, or other charges not fully captured in a simple APR. Always ask lenders for a full breakdown of all costs associated with the loan. These can increase the 'Total Cost' beyond the basic calculation.

  7. Economic Conditions (Inflation & Market Rates):

    Broader economic factors influence interest rates. When inflation is high, central banks may raise interest rates, leading to higher APRs offered by lenders. Conversely, in a slowing economy, rates might decrease. These external conditions affect the 'Annual Interest Rate' you'll likely be offered.

By optimizing factors within your control, like improving your credit score and saving for a larger down payment, you can significantly reduce the financial burden of an auto loan. Always shop around for the best rates and terms. For related information, explore car financing guides.

Frequently Asked Questions (FAQ)

Q1: Does KBB offer its own auto loans?
A1: No, Kelley Blue Book (KBB) is primarily known for providing vehicle valuation data and market insights. They do not directly offer auto loans. A "KBB Auto Loan Calculator" typically refers to a loan calculator that uses standard auto loan formulas, potentially in conjunction with KBB's vehicle pricing information for realistic inputs.
Q2: How accurate is the monthly payment estimate?
A2: The estimate is highly accurate based on the inputs provided (vehicle price, down payment, loan term, and APR). However, the actual loan terms offered by a lender may vary based on your creditworthiness, lender policies, and current market conditions. Always get a final loan estimate from your lender.
Q3: What is considered a "good" interest rate for a car loan?
A3: A "good" interest rate depends heavily on your credit score, the loan term, and the current economic climate. Generally, borrowers with excellent credit (740+) can qualify for rates between 3% to 7%. Rates can be significantly higher for those with lower credit scores. Checking current average rates for your credit profile is recommended.
Q4: Can I use this calculator for a used car?
A4: Yes, absolutely. This calculator is ideal for both new and used car purchases. When buying a used car, you can use KBB's valuation tools to determine a fair market price and then input that price into the calculator along with your loan details.
Q5: Should I aim for a shorter or longer loan term?
A5: This is a trade-off. Shorter terms (e.g., 3-5 years) mean higher monthly payments but much less total interest paid, saving you money in the long run. Longer terms (e.g., 6-7 years) result in lower monthly payments, making the car more affordable month-to-month, but you'll pay significantly more interest overall. The best choice depends on your budget and how long you plan to keep the car.
Q6: What happens if I can't make a monthly payment?
A6: Missing a payment can lead to late fees, damage to your credit score, and potentially repossession of the vehicle. If you anticipate difficulty making payments, contact your lender immediately to discuss potential options, such as deferment or modification of the loan terms.
Q7: How do fees affect the total cost of the loan?
A7: Fees like origination fees, documentation fees, or acquisition fees can increase the total amount you pay. While some might be incorporated into the APR, others are separate. Always ask for a detailed breakdown of all fees associated with the loan to understand the true total cost.
Q8: Can I pay off my car loan early?
A8: Yes, most auto loans allow for early payoff without penalty. Paying off your loan early can save you a substantial amount of interest. Check your loan agreement for any specific clauses regarding early termination fees, though they are uncommon for auto loans.

Related Tools and Internal Resources

Explore these related financial tools and resources to further enhance your car buying and financing journey:

// Function to validate input fields function validateInputs() { var valid = true; var price = parseFloat(document.getElementById("vehiclePrice").value); var downPayment = parseFloat(document.getElementById("downPayment").value); var loanTerm = parseInt(document.getElementById("loanTerm").value); var annualInterestRate = parseFloat(document.getElementById("annualInterestRate").value); // Clear previous errors document.getElementById("vehiclePriceError").style.display = 'none'; document.getElementById("downPaymentError").style.display = 'none'; document.getElementById("loanTermError").style.display = 'none'; document.getElementById("annualInterestRateError").style.display = 'none'; if (isNaN(price) || price <= 0) { document.getElementById("vehiclePriceError").textContent = "Please enter a valid vehicle price."; document.getElementById("vehiclePriceError").style.display = 'block'; valid = false; } if (isNaN(downPayment) || downPayment price) { document.getElementById("downPaymentError").textContent = "Down payment cannot exceed vehicle price."; document.getElementById("downPaymentError").style.display = 'block'; valid = false; } if (isNaN(loanTerm) || loanTerm <= 0) { document.getElementById("loanTermError").textContent = "Please select a valid loan term."; document.getElementById("loanTermError").style.display = 'block'; valid = false; } if (isNaN(annualInterestRate) || annualInterestRate <= 0) { document.getElementById("annualInterestRateError").textContent = "Please enter a valid annual interest rate (e.g., 5.5)."; document.getElementById("annualInterestRateError").style.display = 'block'; valid = false; } // Check if loan amount after down payment is positive var loanAmountCheck = price – downPayment; if (loanAmountCheck 0) { // Allow 0 loan amount if price is 0 (edge case) document.getElementById("downPaymentError").textContent = "Down payment cannot exceed vehicle price."; document.getElementById("downPaymentError").style.display = 'block'; valid = false; } return valid; } // Function to calculate loan details function calculateLoan() { if (!validateInputs()) { document.getElementById('resultsContainer').style.display = 'none'; return; } var vehiclePrice = parseFloat(document.getElementById("vehiclePrice").value); var downPayment = parseFloat(document.getElementById("downPayment").value); var loanTermYears = parseInt(document.getElementById("loanTerm").value); var annualInterestRate = parseFloat(document.getElementById("annualInterestRate").value); var loanAmount = vehiclePrice – downPayment; var monthlyInterestRate = (annualInterestRate / 100) / 12; var numberOfPayments = loanTermYears * 12; var monthlyPayment = 0; var totalInterestPaid = 0; var totalCost = 0; if (loanAmount > 0 && monthlyInterestRate > 0 && numberOfPayments > 0) { // Standard loan payment formula M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1] monthlyPayment = loanAmount * (monthlyInterestRate * Math.pow(1 + monthlyInterestRate, numberOfPayments)) / (Math.pow(1 + monthlyInterestRate, numberOfPayments) – 1); totalInterestPaid = (monthlyPayment * numberOfPayments) – loanAmount; totalCost = loanAmount + totalInterestPaid; } else if (loanAmount === 0) { monthlyPayment = 0; totalInterestPaid = 0; totalCost = 0; } else { // Handle cases like 0 interest rate (simple division) or other edge cases if (monthlyInterestRate === 0 && loanAmount > 0) { monthlyPayment = loanAmount / numberOfPayments; totalInterestPaid = 0; totalCost = loanAmount; } else if (loanAmount > 0 && numberOfPayments > 0) { // Fallback for potential edge cases, though ideally handled above monthlyPayment = loanAmount / numberOfPayments; // Simplified if rate is effectively 0 or calculation fails totalInterestPaid = 0; totalCost = loanAmount; } } // Format currency values var formattedMonthlyPayment = monthlyPayment.toLocaleString('en-US', { style: 'currency', currency: 'USD' }); var formattedTotalInterestPaid = totalInterestPaid.toLocaleString('en-US', { style: 'currency', currency: 'USD' }); var formattedTotalCost = totalCost.toLocaleString('en-US', { style: 'currency', currency: 'USD' }); var formattedLoanAmount = loanAmount.toLocaleString('en-US', { style: 'currency', currency: 'USD' }); // Display results document.getElementById("mainResult").textContent = formattedMonthlyPayment; document.getElementById("totalInterestPaid").textContent = formattedTotalInterestPaid; document.getElementById("totalCost").textContent = formattedTotalCost; document.getElementById("loanAmountResult").textContent = formattedLoanAmount; document.getElementById('resultsContainer').style.display = 'block'; // Update amortization table and chart updateAmortization(loanAmount, monthlyInterestRate, numberOfPayments, monthlyPayment); updateChart(loanAmount, totalInterestPaid, monthlyPayment, numberOfPayments); } // Function to reset calculator to default values function resetCalculator() { document.getElementById("vehiclePrice").value = "30000"; document.getElementById("downPayment").value = "5000"; document.getElementById("loanTerm").value = "5"; document.getElementById("annualInterestRate").value = "6.5"; // Clear errors document.getElementById("vehiclePriceError").style.display = 'none'; document.getElementById("downPaymentError").style.display = 'none'; document.getElementById("loanTermError").style.display = 'none'; document.getElementById("annualInterestRateError").style.display = 'none'; // Clear results document.getElementById('resultsContainer').style.display = 'none'; document.getElementById("mainResult").textContent = "$0.00"; document.getElementById("totalInterestPaid").textContent = "$0.00"; document.getElementById("totalCost").textContent = "$0.00"; document.getElementById("loanAmountResult").textContent = "$0.00"; // Clear table and chart clearAmortizationTable(); clearChart(); } // Function to copy results function copyResults() { var monthlyPayment = document.getElementById("mainResult").textContent; var totalInterestPaid = document.getElementById("totalInterestPaid").textContent; var totalCost = document.getElementById("totalCost").textContent; var loanAmount = document.getElementById("loanAmountResult").textContent; var vehiclePrice = document.getElementById("vehiclePrice").value; var downPayment = document.getElementById("downPayment").value; var loanTerm = document.getElementById("loanTerm").options[document.getElementById("loanTerm").selectedIndex].text; var annualInterestRate = document.getElementById("annualInterestRate").value; var assumptions = `Key Assumptions:\n` + `Vehicle Price: $${vehiclePrice}\n` + `Down Payment: $${downPayment}\n` + `Loan Term: ${loanTerm}\n` + `Annual Interest Rate: ${annualInterestRate}%\n`; var resultsText = `Estimated Loan Results:\n` + `Monthly Payment: ${monthlyPayment}\n` + `Total Interest Paid: ${totalInterestPaid}\n` + `Total Cost: ${totalCost}\n` + `Loan Amount: ${loanAmount}\n\n` + assumptions; // Use Clipboard API if available, fallback to prompt if (navigator.clipboard) { navigator.clipboard.writeText(resultsText).then(function() { alert('Results copied to clipboard!'); }).catch(function(err) { console.error('Failed to copy text: ', err); // Fallback if clipboard API fails prompt("Copy this text:", resultsText); }); } else { prompt("Copy this text:", resultsText); } } // — Amortization Table Logic — function updateAmortization(loanAmount, monthlyInterestRate, numberOfPayments, monthlyPayment) { var tableBody = document.getElementById("amortizationTableBody"); if (!tableBody) return; // Ensure table exists // Clear previous table data tableBody.innerHTML = "; var remainingBalance = loanAmount; var paymentNumber = 1; var amortizationData = []; // To store data for chart while (remainingBalance > 0.01 && paymentNumber remainingBalance) { principalForMonth = remainingBalance; monthlyPayment = interestForMonth + principalForMonth; // Adjust monthly payment for the last installment } remainingBalance -= principalForMonth; // Ensure remaining balance doesn't go negative due to rounding if (remainingBalance 0) { for (var i = 0; i 0.01 && paymentNum balance) { principalThisMonth = balance; } balance -= principalThisMonth; if (balance < 0) balance = 0; principalData.push(principalThisMonth); interestData.push(interestThisMonth); paymentNum++; } } // Create new chart myChart = new Chart(ctx, { type: 'bar', // Using bar chart for clarity of principal vs interest per month data: { labels: labels, datasets: [{ label: 'Principal Paid Per Month', data: principalData, backgroundColor: 'rgba(0, 74, 153, 0.6)', // Primary color variation borderColor: 'rgba(0, 74, 153, 1)', borderWidth: 1 }, { label: 'Interest Paid Per Month', data: interestData, backgroundColor: 'rgba(40, 167, 69, 0.6)', // Success color variation borderColor: 'rgba(40, 167, 69, 1)', borderWidth: 1 }] }, options: { responsive: true, maintainAspectRatio: false, // Allows chart to resize freely within its container scales: { x: { stacked: true, // Stack bars for principal and interest title: { display: true, text: 'Payment Period (Months)' } }, y: { stacked: true, beginAtZero: true, title: { display: true, text: 'Amount ($)' }, ticks: { // Format y-axis ticks as currency callback: function(value, index, values) { return '$' + value.toLocaleString(); } } } }, plugins: { tooltip: { callbacks: { label: function(context) { var label = context.dataset.label || ''; if (label) { label += ': '; } if (context.parsed.y !== null) { label += new Intl.NumberFormat('en-US', { style: 'currency', currency: 'USD' }).format(context.parsed.y); } return label; } } } } } }); } function clearChart() { var ctx = document.getElementById('loanChart').getContext('2d'); if (myChart) { myChart.destroy(); myChart = null; // Reset chart instance } // Optionally clear canvas context if needed, but destroy usually handles it ctx.clearRect(0, 0, ctx.canvas.width, ctx.canvas.height); } // Initial calculation on page load document.addEventListener('DOMContentLoaded', function() { // Add the table structure initially hidden var tableHtml = `
Loan Amortization Schedule
Payment # Monthly Payment Interest Paid Principal Paid Remaining Balance
`; document.getElementById('loanCalculator').insertAdjacentHTML('afterend', tableHtml); // Add the chart structure initially hidden var chartHtml = `
Monthly Breakdown of Principal vs. Interest
`; document.getElementById('loanCalculator').insertAdjacentHTML('afterend', chartHtml); calculateLoan(); // Perform initial calculation to populate results, table, and chart });

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