Loan Calculator to Pay off Early

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Loan Calculator to Pay Off Early

Strategize your debt repayment and save money

Calculate Your Accelerated Loan Payoff

Enter your loan details and see how extra payments can help you pay off your loan faster and save on interest.

The total amount you owe on the loan.
The yearly interest rate for your loan.
Your regular monthly payment amount.
Additional amount you can pay each month.

Your Payoff Summary

Total Interest Saved

Original Term (Months)

New Term (Months)

Total Paid

How it works: This calculator determines your original loan term and total interest based on your current loan details. Then, it calculates the new payoff timeline and total interest paid when you add an extra monthly payment. The difference in total interest is your savings.

What is a Loan Calculator to Pay Off Early?

A loan calculator to pay off early is a specialized financial tool designed to help individuals understand the impact of making additional payments beyond their minimum required amount on a loan. It allows users to input their current loan details, such as the principal balance, interest rate, and monthly payment, and then simulate the effect of adding a specific extra amount each month. The primary goal of using such a calculator is to visualize how these accelerated payments can shorten the loan's repayment period and significantly reduce the total interest paid over the life of the loan. This empowers borrowers to make informed decisions about their debt management strategies, potentially saving thousands of dollars and achieving financial freedom sooner.

Who should use it: Anyone with an outstanding loan, including mortgages, auto loans, personal loans, or student loans, can benefit from this calculator. It's particularly useful for individuals who have received a financial windfall (like a bonus or tax refund), have extra disposable income, or are simply motivated to become debt-free faster. It helps answer the crucial question: "If I pay an extra $X per month, how much faster will I pay off my loan, and how much interest will I save?"

Common misconceptions: A frequent misconception is that extra payments are applied directly to the principal balance without affecting the interest calculation for the current period. While most lenders apply extra payments to the principal, the interest for the *next* period is calculated on the *new, reduced* principal. Another misunderstanding is underestimating the power of small, consistent extra payments; even modest additional amounts can lead to substantial savings over time due to the compounding nature of interest. Some also believe that only large, lump-sum payments make a difference, overlooking the cumulative effect of regular, smaller extra payments.

Loan Calculator to Pay Off Early Formula and Mathematical Explanation

The core of a loan calculator to pay off early involves comparing two scenarios: the standard repayment schedule and an accelerated repayment schedule. The calculations rely on standard loan amortization formulas.

Scenario 1: Original Loan Amortization

First, we need to determine the original loan term and total interest paid under the standard monthly payment. The standard monthly payment (M) for an amortizing loan is calculated using the following formula:

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

Where:

  • M = Monthly Payment
  • P = Principal Loan Amount
  • i = Monthly Interest Rate (Annual Rate / 12)
  • n = Total Number of Payments (Loan Term in Months)

However, in this calculator, we are given the monthly payment and need to find the term (n). This requires solving the formula for 'n', which is complex. A more practical approach for calculators is iterative calculation or using a financial function that solves for 'n'. For simplicity in explanation, we'll assume we can calculate the original term and interest.

The total interest paid is calculated as: Total Interest = (M * n) - P

Scenario 2: Accelerated Loan Payoff

When an extra monthly payment is introduced, the new total monthly payment becomes M_new = M + Extra_Payment.

The calculator then determines the new number of payments (n_new) required to pay off the loan with this higher payment amount. Again, this involves solving for 'n' in the amortization formula with the new payment amount.

The total amount paid under the accelerated plan is: Total Paid (New) = M_new * n_new

The total interest paid under the accelerated plan is: Total Interest (New) = Total Paid (New) - P

The total interest saved is the difference between the two scenarios:

Total Interest Saved = Total Interest (Original) - Total Interest (New)

Variables Table

Loan Payoff Variables
Variable Meaning Unit Typical Range
P (Loan Amount) The initial amount borrowed. Currency ($) $1,000 – $1,000,000+
Annual Interest Rate The yearly rate charged on the loan. Percentage (%) 1% – 30%+
i (Monthly Interest Rate) Annual rate divided by 12. Decimal 0.00083 – 0.025+
M (Current Monthly Payment) The fixed amount paid each month. Currency ($) $50 – $5,000+
Extra Monthly Payment Additional amount paid voluntarily each month. Currency ($) $0 – $1,000+
n (Original Loan Term) Total number of months to repay the loan originally. Months 12 – 360+
n_new (New Loan Term) Total number of months to repay with extra payments. Months Less than n
Total Interest Saved Difference in total interest paid between scenarios. Currency ($) $0 – $100,000+

Practical Examples (Real-World Use Cases)

Example 1: Accelerating a Car Loan Payoff

Scenario: Sarah has a $15,000 car loan with a 5% annual interest rate. Her current monthly payment is $300, and the original loan term was 60 months. She decides she can afford to pay an extra $100 per month.

Inputs:

  • Loan Amount: $15,000
  • Annual Interest Rate: 5%
  • Current Monthly Payment: $300
  • Extra Monthly Payment: $100

Calculator Output (Simulated):

  • Original Loan Term: 52 months
  • Original Total Interest Paid: ~$3,000
  • New Monthly Payment: $400 ($300 + $100)
  • New Loan Term: 39 months
  • New Total Interest Paid: ~$1,800
  • Total Interest Saved: ~$1,200

Financial Interpretation: By paying an extra $100 per month, Sarah will pay off her car loan 13 months earlier (52 – 39) and save approximately $1,200 in interest. This demonstrates the significant benefit of consistent extra payments, even on a relatively smaller loan.

Example 2: Aggressively Paying Down a Mortgage

Scenario: Mark and Lisa have a $250,000 mortgage balance remaining on their home. The current interest rate is 4%, and their minimum monthly payment is $1,200. They receive an inheritance and decide to allocate an extra $500 per month towards the mortgage principal.

Inputs:

  • Loan Amount: $250,000
  • Annual Interest Rate: 4%
  • Current Monthly Payment: $1,200
  • Extra Monthly Payment: $500

Calculator Output (Simulated):

  • Original Loan Term: (Assuming ~25 years remaining) ~300 months
  • Original Total Interest Paid: (Over remaining term) ~$110,000
  • New Monthly Payment: $1,700 ($1,200 + $500)
  • New Loan Term: 175 months
  • New Total Interest Paid: ~$65,000
  • Total Interest Saved: ~$45,000

Financial Interpretation: Adding $500 per month to their mortgage payment will allow Mark and Lisa to pay off their loan approximately 125 months (over 10 years) sooner. More impressively, they will save around $45,000 in interest. This highlights the immense power of extra payments on large, long-term debts like mortgages.

How to Use This Loan Calculator to Pay Off Early

Using the loan calculator to pay off early is straightforward. Follow these steps to get personalized insights into your debt repayment strategy:

  1. Enter Loan Amount: Input the total outstanding balance of your loan in the "Loan Amount ($)" field.
  2. Input Interest Rate: Enter the annual interest rate of your loan in the "Annual Interest Rate (%)" field. Ensure you use the correct percentage.
  3. Specify Current Monthly Payment: Enter the exact amount of your regular, minimum monthly payment in the "Current Monthly Payment ($)" field.
  4. Add Extra Payment Amount: In the "Extra Monthly Payment ($)" field, enter the additional amount you plan to pay each month. If you don't plan to pay extra, leave this at $0.
  5. Click Calculate: Press the "Calculate Payoff" button.

How to read results:

  • Total Interest Saved: This is the primary result, displayed prominently. It shows the total amount of money you will save on interest by making the extra payments.
  • Original Loan Term (Months): This indicates how long it would take to pay off the loan making only the minimum payments.
  • New Loan Term (Months): This shows the reduced number of months it will take to pay off the loan with the added extra payments.
  • Total Paid: This is the sum of all payments (principal + interest) made under the accelerated payoff plan.
  • Key Assumptions: The calculator assumes your interest rate remains fixed, extra payments are applied directly to the principal, and you consistently make the specified extra payments every month.

Decision-making guidance: Use the "Total Interest Saved" figure to gauge the financial benefit. A larger saving might motivate you to find ways to increase your extra payments. Compare the "New Loan Term" to your original term to see how much time you'll shave off. If the savings and time reduction are significant, consider prioritizing these extra payments. Use the "Copy Results" button to save or share your findings. Remember to consult with a financial advisor for personalized advice tailored to your specific situation.

Key Factors That Affect Loan Payoff Results

Several factors significantly influence how much time and money you can save by paying off a loan early. Understanding these is crucial for effective debt management:

  1. Interest Rate: This is arguably the most critical factor. Higher interest rates mean more of your payment goes towards interest, and less towards principal. Therefore, extra payments on high-interest loans yield much larger savings in both time and money compared to low-interest loans. A personal loan calculator can help illustrate this.
  2. Loan Balance: A larger outstanding loan balance naturally means more interest accrues over time. Extra payments on larger balances have a more substantial impact on reducing the overall interest paid and shortening the loan term.
  3. Loan Term (Original): Loans with longer original terms (like mortgages) offer more opportunities for interest to accumulate. Paying extra on a long-term loan can lead to dramatic reductions in the repayment period and substantial interest savings.
  4. Consistency of Extra Payments: The calculator assumes consistent extra payments. Irregular or missed extra payments will reduce the overall savings and the projected payoff acceleration. Small, consistent additions often outperform large, infrequent ones.
  5. Loan Type and Fees: Some loans have prepayment penalties, which can negate the benefits of paying early. Always check your loan agreement. Additionally, the type of loan matters; prioritizing high-interest debt (like credit cards) over low-interest debt (like some mortgages) is generally a sound financial strategy. Use a debt snowball vs avalanche calculator to compare payoff methods.
  6. Inflation and Opportunity Cost: While paying off debt is good, consider the opportunity cost. If you have a very low-interest loan (e.g., 2-3%) and could potentially earn a higher return by investing that extra money (e.g., in stocks), it might be financially optimal to invest instead. Inflation also erodes the value of future debt payments, making them effectively cheaper over time.
  7. Cash Flow and Emergency Fund: Before committing to extra payments, ensure you have a solid emergency fund. Unexpected expenses can force you to take on new, potentially higher-interest debt if you deplete your savings. Maintaining healthy cash flow is paramount.

Frequently Asked Questions (FAQ)

Q1: How do extra payments actually reduce the total interest paid?

A: When you make an extra payment, it's typically applied directly to your loan's principal balance. This reduces the amount of money your lender calculates interest on for the *next* billing cycle. By lowering the principal faster, you pay less interest over the remaining life of the loan.

Q2: Does it matter if I pay extra at the beginning or end of the loan term?

A: Yes, paying extra earlier in the loan term has a much greater impact. This is because the principal balance is highest at the beginning, meaning more interest accrues. Extra payments made early reduce this large principal faster, leading to significantly larger interest savings over the long run.

Q3: What if my loan has a prepayment penalty?

A: Some loans, particularly certain mortgages or auto loans, may charge a fee if you pay them off early or make significant extra payments. Always check your loan agreement for any prepayment penalties. If a penalty exists, calculate if the interest savings outweigh the penalty cost.

Q4: Should I pay extra on my mortgage or my student loans first?

A: Generally, it's financially optimal to prioritize paying extra on the loan with the highest interest rate first (the "avalanche" method). This maximizes your interest savings. However, some people prefer the psychological boost of paying off smaller debts completely first (the "snowball" method), even if it costs slightly more in interest.

Q5: Can I use a lump sum payment (like a bonus) instead of monthly extra payments?

A: Absolutely! A lump sum payment can significantly accelerate your payoff. Apply it directly to the principal. The calculator can simulate this by setting the "Extra Monthly Payment" to $0 and then calculating the effect of a large, one-time payment (though this specific calculator focuses on monthly additions).

Q6: How do I ensure my extra payment is applied to the principal?

A: When making an extra payment, clearly indicate to your lender that the additional amount is to be applied to the principal balance. Some lenders require you to specify this online or via phone. If you don't specify, it might be applied towards future interest or payments, reducing the benefit.

Q7: What's the difference between this calculator and a standard loan payment calculator?

A: A standard loan payment calculator typically helps you determine your monthly payment based on loan amount, rate, and term, or vice versa. This calculator specifically focuses on the *impact of additional payments* to show how you can pay off a loan faster and save interest.

Q8: Is it always better to pay off debt early?

A: While paying off debt early generally improves your financial health by reducing interest costs and freeing up cash flow, it's not always the absolute best strategy. Consider the opportunity cost: could you earn a higher return by investing the money? Also, ensure you maintain an adequate emergency fund before aggressively paying down low-interest debt.

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function calculateLoanPayoff() { // Get input values var loanAmount = parseFloat(document.getElementById("loanAmount").value); var interestRate = parseFloat(document.getElementById("interestRate").value); var currentMonthlyPayment = parseFloat(document.getElementById("currentMonthlyPayment").value); var extraMonthlyPayment = parseFloat(document.getElementById("extraMonthlyPayment").value); // Clear previous errors document.getElementById("loanAmountError").textContent = ""; document.getElementById("interestRateError").textContent = ""; document.getElementById("currentMonthlyPaymentError").textContent = ""; document.getElementById("extraMonthlyPaymentError").textContent = ""; // Validate inputs var isValid = true; if (isNaN(loanAmount) || loanAmount <= 0) { document.getElementById("loanAmountError").textContent = "Please enter a valid loan amount."; isValid = false; } if (isNaN(interestRate) || interestRate < 0) { document.getElementById("interestRateError").textContent = "Please enter a valid interest rate."; isValid = false; } if (isNaN(currentMonthlyPayment) || currentMonthlyPayment <= 0) { document.getElementById("currentMonthlyPaymentError").textContent = "Please enter a valid current monthly payment."; isValid = false; } if (isNaN(extraMonthlyPayment) || extraMonthlyPayment 0) { // Solve for n (number of payments) using the loan payment formula rearranged // M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1] // This is complex to solve directly for n. Iterative approach is more practical. // Let's simulate month by month to find the term. var tempBalance = loanAmount; var months = 0; while (tempBalance > 0.01) { // Use a small threshold for floating point precision var interestForMonth = tempBalance * monthlyInterestRate; var principalForMonth = originalMonthlyPayment – interestForMonth; if (principalForMonth 10000) { // Safety break for extremely long terms originalTermMonths = Infinity; originalTotalInterest = Infinity; originalTotalPaid = Infinity; break; } } if (originalTermMonths !== Infinity) { originalTermMonths = months; originalTotalPaid = originalMonthlyPayment * originalTermMonths; originalTotalInterest = originalTotalPaid – loanAmount; } } else { // 0% interest rate originalTermMonths = Math.ceil(loanAmount / originalMonthlyPayment); originalTotalInterest = 0; originalTotalPaid = loanAmount; } // — Calculate New Loan Term and Interest with Extra Payment — var newTermMonths = 0; var newTotalInterest = 0; var newTotalPaid = 0; if (newMonthlyPayment > originalMonthlyPayment) { // Only calculate if extra payment is made if (monthlyInterestRate > 0) { var tempBalance = loanAmount; var months = 0; while (tempBalance > 0.01) { var interestForMonth = tempBalance * monthlyInterestRate; var principalForMonth = newMonthlyPayment – interestForMonth; if (principalForMonth 10000) { // Safety break newTermMonths = Infinity; newTotalInterest = Infinity; newTotalPaid = Infinity; break; } } if (newTermMonths !== Infinity) { newTermMonths = months; newTotalPaid = newMonthlyPayment * newTermMonths; newTotalInterest = newTotalPaid – loanAmount; } } else { // 0% interest rate newTermMonths = Math.ceil(loanAmount / newMonthlyPayment); newTotalInterest = 0; newTotalPaid = loanAmount; } } else { // No extra payment, results are same as original newTermMonths = originalTermMonths; newTotalInterest = originalTotalInterest; newTotalPaid = originalTotalPaid; } // — Calculate Total Interest Saved — var totalInterestSaved = 0; if (originalTotalInterest !== Infinity && newTotalInterest !== Infinity) { totalInterestSaved = originalTotalInterest – newTotalInterest; } else if (originalTotalInterest === Infinity) { totalInterestSaved = Infinity; // Cannot save if original is unpayable } else { totalInterestSaved = Infinity; // Saving is infinite if new is unpayable but original is not } // Display results document.getElementById("totalSavings").textContent = formatCurrency(totalInterestSaved); document.getElementById("originalLoanTerm").textContent = isFinite(originalTermMonths) ? originalTermMonths : "N/A"; document.getElementById("newLoanTerm").textContent = isFinite(newTermMonths) ? newTermMonths : "N/A"; document.getElementById("totalPaid").textContent = formatCurrency(newTotalPaid); // Update chart data updateChart(loanAmount, monthlyInterestRate, originalMonthlyPayment, newMonthlyPayment, isFinite(originalTermMonths) ? originalTermMonths : 1000, isFinite(newTermMonths) ? newTermMonths : 1000); updateTable(loanAmount, monthlyInterestRate, originalMonthlyPayment, newMonthlyPayment, isFinite(originalTermMonths) ? originalTermMonths : 1000, isFinite(newTermMonths) ? newTermMonths : 1000); } function formatCurrency(amount) { if (amount === Infinity) return "Infinite"; if (isNaN(amount) || amount < 0) return "$–"; return "$" + amount.toFixed(2).replace(/\d(?=(\d{3})+\.)/g, '$&,'); } function formatNumber(num) { if (isNaN(num)) return "–"; return num.toFixed(2); } function resetForm() { document.getElementById("loanAmount").value = ""; document.getElementById("interestRate").value = ""; document.getElementById("currentMonthlyPayment").value = ""; document.getElementById("extraMonthlyPayment").value = "0"; document.getElementById("loanAmountError").textContent = ""; document.getElementById("interestRateError").textContent = ""; document.getElementById("currentMonthlyPaymentError").textContent = ""; document.getElementById("extraMonthlyPaymentError").textContent = ""; document.getElementById("totalSavings").textContent = "–"; document.getElementById("originalLoanTerm").textContent = "–"; document.getElementById("newLoanTerm").textContent = "–"; document.getElementById("totalPaid").textContent = "–"; // Clear chart and table clearChart(); clearTable(); } function copyResults() { var loanAmount = document.getElementById("loanAmount").value; var interestRate = document.getElementById("interestRate").value; var currentMonthlyPayment = document.getElementById("currentMonthlyPayment").value; var extraMonthlyPayment = document.getElementById("extraMonthlyPayment").value; var totalSavings = document.getElementById("totalSavings").textContent; var originalLoanTerm = document.getElementById("originalLoanTerm").textContent; var newLoanTerm = document.getElementById("newLoanTerm").textContent; var totalPaid = document.getElementById("totalPaid").textContent; var assumptions = "Key Assumptions:\n" + "- Loan Amount: $" + loanAmount + "\n" + "- Annual Interest Rate: " + interestRate + "%\n" + "- Current Monthly Payment: $" + currentMonthlyPayment + "\n" + "- Extra Monthly Payment: $" + extraMonthlyPayment; var resultsText = "Loan Payoff Summary:\n" + "Total Interest Saved: " + totalSavings + "\n" + "Original Loan Term: " + originalLoanTerm + " months\n" + "New Loan Term: " + newLoanTerm + " months\n" + "Total Paid: " + totalPaid + "\n\n" + assumptions; // Use a temporary textarea to copy text var textArea = document.createElement("textarea"); textArea.value = resultsText; textArea.style.position = "fixed"; textArea.style.left = "-9999px"; document.body.appendChild(textArea); textArea.focus(); textArea.select(); try { var successful = document.execCommand('copy'); var msg = successful ? 'Results copied!' : 'Failed to copy results.'; alert(msg); } catch (err) { alert('Failed to copy results.'); } document.body.removeChild(textArea); } // — Charting Logic — var myChart; var chartCanvas = document.getElementById('payoffChart'); if (chartCanvas) { var ctx = chartCanvas.getContext('2d'); myChart = new Chart(ctx, { type: 'line', data: { labels: [], datasets: [{ label: 'Original Loan Balance', data: [], borderColor: 'rgba(0, 74, 153, 1)', backgroundColor: 'rgba(0, 74, 153, 0.1)', fill: false, tension: 0.1 }, { label: 'Accelerated Loan Balance', data: [], borderColor: 'rgba(40, 167, 69, 1)', backgroundColor: 'rgba(40, 167, 69, 0.1)', fill: false, tension: 0.1 }] }, options: { responsive: true, maintainAspectRatio: false, scales: { y: { beginAtZero: true, title: { display: true, text: 'Loan Balance ($)' } }, x: { title: { display: true, text: 'Month' } } }, plugins: { tooltip: { mode: 'index', intersect: false, }, title: { display: true, text: 'Loan Balance Over Time' } }, hover: { mode: 'nearest', intersect: true } } }); } function updateChart(loanAmount, monthlyInterestRate, originalMonthlyPayment, newMonthlyPayment, originalMaxMonths, newMaxMonths) { if (!myChart) return; var maxMonths = Math.max(originalMaxMonths, newMaxMonths, 50); // Ensure chart has reasonable length var labels = []; var originalBalanceData = []; var acceleratedBalanceData = []; var tempBalanceOriginal = loanAmount; var tempBalanceAccelerated = loanAmount; for (var i = 0; i <= maxMonths; i++) { labels.push(i); // Original Balance Calculation if (i === 0) { originalBalanceData.push(loanAmount); } else { var interestOriginal = tempBalanceOriginal * monthlyInterestRate; var principalOriginal = originalMonthlyPayment – interestOriginal; if (principalOriginal <= 0 || tempBalanceOriginal <= 0.01) { tempBalanceOriginal = 0; // Loan paid off or payment insufficient } else { tempBalanceOriginal -= principalOriginal; } originalBalanceData.push(Math.max(0, tempBalanceOriginal)); // Ensure balance doesn't go below 0 } // Accelerated Balance Calculation if (i === 0) { acceleratedBalanceData.push(loanAmount); } else { var interestAccelerated = tempBalanceAccelerated * monthlyInterestRate; var principalAccelerated = newMonthlyPayment – interestAccelerated; if (principalAccelerated <= 0 || tempBalanceAccelerated <= 0.01) { tempBalanceAccelerated = 0; // Loan paid off or payment insufficient } else { tempBalanceAccelerated -= principalAccelerated; } acceleratedBalanceData.push(Math.max(0, tempBalanceAccelerated)); // Ensure balance doesn't go below 0 } // Stop if both balances are zero if (tempBalanceOriginal <= 0.01 && tempBalanceAccelerated 0) { // Fill remaining labels with 0 if needed, up to maxMonths for (var j = i + 1; j <= maxMonths; j++) { labels.push(j); originalBalanceData.push(0); acceleratedBalanceData.push(0); } break; } } myChart.data.labels = labels; myChart.data.datasets[0].data = originalBalanceData; myChart.data.datasets[1].data = acceleratedBalanceData; myChart.update(); } function clearChart() { if (myChart) { myChart.data.labels = []; myChart.data.datasets[0].data = []; myChart.data.datasets[1].data = []; myChart.update(); } } // — Table Logic — function updateTable(loanAmount, monthlyInterestRate, originalMonthlyPayment, newMonthlyPayment, originalMaxMonths, newMaxMonths) { var tableBody = document.getElementById("amortizationTableBody"); if (!tableBody) { // Create table if it doesn't exist var tableHtml = ` Amortization Schedule Comparison Month Original Balance Original Payment Accelerated Balance Accelerated Payment `; var tableContainer = document.createElement('div'); tableContainer.style.overflowX = 'auto'; // Make table scrollable tableContainer.innerHTML = tableHtml; document.getElementById('results').insertAdjacentElement('afterend', tableContainer.firstChild); // Insert after results section tableBody = document.getElementById("amortizationTableBody"); } tableBody.innerHTML = "; // Clear existing rows var maxMonths = Math.max(originalMaxMonths, newMaxMonths, 12); // Show at least 12 months or up to payoff var tempBalanceOriginal = loanAmount; var tempBalanceAccelerated = loanAmount; for (var i = 0; i 0 && originalBalance > 0) ? originalBalance * monthlyInterestRate : 0; var originalPrincipal = (i > 0 && originalBalance > 0) ? originalMonthlyPayment – originalInterest : 0; if (originalPrincipal > originalBalance) originalPrincipal = originalBalance; // Adjust last payment var acceleratedInterest = (i > 0 && acceleratedBalance > 0) ? acceleratedBalance * monthlyInterestRate : 0; var acceleratedPrincipal = (i > 0 && acceleratedBalance > 0) ? newMonthlyPayment – acceleratedInterest : 0; if (acceleratedPrincipal > acceleratedBalance) acceleratedPrincipal = acceleratedBalance; // Adjust last payment var row = tableBody.insertRow(); row.insertCell(0).textContent = i === 0 ? "Start" : i; row.insertCell(1).textContent = formatCurrency(originalBalance); row.insertCell(2).textContent = (i === 0) ? "" : formatCurrency(originalMonthlyPayment); row.insertCell(3).textContent = formatCurrency(acceleratedBalance); row.insertCell(4).textContent = (i === 0) ? "" : formatCurrency(newMonthlyPayment); // Update balances for next iteration if (i > 0) { tempBalanceOriginal -= originalPrincipal; tempBalanceAccelerated -= acceleratedPrincipal; } // Stop if both loans are paid off if (tempBalanceOriginal <= 0.01 && tempBalanceAccelerated 0) { break; } } } function clearTable() { var tableContainer = document.querySelector("#results + div > table"); // Find the table container added by updateTable if (tableContainer) { tableContainer.remove(); } } function toggleFaq(element) { var paragraph = element.nextElementSibling; if (paragraph.style.display === "block") { paragraph.style.display = "none"; } else { paragraph.style.display = "block"; } } // Initial calculation on load if default values are present document.addEventListener('DOMContentLoaded', function() { // Check if inputs have values to trigger calculation if (document.getElementById("loanAmount").value && document.getElementById("interestRate").value && document.getElementById("currentMonthlyPayment").value) { calculateLoanPayoff(); } }); // Add a canvas element for the chart dynamically var chartContainer = document.createElement('div'); chartContainer.className = 'chart-container'; chartContainer.innerHTML = 'Visualizing the reduction in loan balance over time with accelerated payments.'; document.querySelector('.article-content').insertAdjacentElement('afterbegin', chartContainer);

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