401 Loan Calculator

401(k) Loan Calculator: Estimate Repayments & Impact :root { –primary-color: #004a99; –success-color: #28a745; –background-color: #f8f9fa; –text-color: #333; –border-color: #ddd; –card-bg: #fff; –shadow: 0 2px 10px 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); line-height: 1.6; margin: 0; padding: 0; } .container { max-width: 1000px; margin: 20px auto; padding: 20px; background-color: var(–card-bg); border-radius: 8px; box-shadow: var(–shadow); } h1, h2, h3 { color: var(–primary-color); text-align: center; margin-bottom: 1.5em; } h1 { font-size: 2.2em; } h2 { font-size: 1.8em; border-bottom: 2px solid var(–primary-color); padding-bottom: 0.5em; margin-top: 2em; } h3 { font-size: 1.4em; margin-top: 1.5em; color: var(–primary-color); } .loan-calc-container { background-color: var(–card-bg); padding: 30px; border-radius: 8px; box-shadow: var(–shadow); margin-bottom: 30px; } .input-group { margin-bottom: 20px; text-align: left; } .input-group label { display: block; margin-bottom: 8px; font-weight: bold; color: var(–primary-color); } .input-group input[type="number"], .input-group input[type="range"], .input-group select { width: calc(100% – 24px); padding: 12px; border: 1px solid var(–border-color); border-radius: 5px; font-size: 1em; margin-top: 5px; box-sizing: border-box; } .input-group input[type="range"] { width: 100%; cursor: pointer; } .input-group .helper-text { font-size: 0.85em; color: #666; margin-top: 5px; display: block; } .error-message { color: #dc3545; font-size: 0.9em; margin-top: 5px; min-height: 1.2em; } .results-container { background-color: var(–primary-color); color: #fff; padding: 30px; border-radius: 8px; margin-top: 30px; box-shadow: var(–shadow); text-align: center; } .results-container h3 { color: #fff; margin-bottom: 15px; } .primary-result { font-size: 2.5em; font-weight: bold; margin-bottom: 10px; padding: 10px 15px; background-color: var(–success-color); border-radius: 5px; display: inline-block; } .secondary-results { display: flex; justify-content: space-around; flex-wrap: wrap; margin-top: 25px; gap: 15px; } .secondary-result-item { background-color: rgba(255, 255, 255, 0.15); padding: 15px 20px; border-radius: 5px; text-align: center; flex: 1; min-width: 180px; } .secondary-result-item h4 { margin: 0 0 10px 0; font-size: 1.1em; color: #eee; } .secondary-result-item .value { font-size: 1.8em; font-weight: bold; color: #fff; } .formula-explanation { background-color: #e9ecef; color: #444; padding: 15px; border-radius: 5px; margin-top: 20px; font-size: 0.95em; border-left: 4px solid var(–primary-color); } .formula-explanation strong { color: var(–primary-color); } .button-group { display: flex; justify-content: center; gap: 15px; margin-top: 30px; flex-wrap: wrap; } button { background-color: var(–primary-color); color: white; border: none; padding: 12px 25px; border-radius: 5px; font-size: 1em; cursor: pointer; transition: background-color 0.3s ease; font-weight: bold; } button:hover { background-color: #003366; } button.reset { background-color: #6c757d; } button.reset:hover { background-color: #5a6268; } button.copy { background-color: var(–success-color); } button.copy:hover { background-color: #1e7e34; } table { width: 100%; border-collapse: collapse; margin-top: 30px; margin-bottom: 30px; box-shadow: var(–shadow); } th, td { padding: 12px 15px; text-align: left; border: 1px solid var(–border-color); } thead { background-color: var(–primary-color); color: white; } tbody tr:nth-child(even) { background-color: #f2f2f2; } caption { font-size: 1.1em; font-weight: bold; color: var(–primary-color); margin-bottom: 10px; text-align: left; } canvas { display: block; margin: 30px auto; border: 1px solid var(–border-color); border-radius: 5px; background-color: var(–card-bg); } .article-content { margin-top: 50px; background-color: var(–card-bg); padding: 30px; border-radius: 8px; box-shadow: var(–shadow); text-align: left; } .article-content p { margin-bottom: 1.2em; } .article-content a { color: var(–primary-color); text-decoration: none; } .article-content a:hover { text-decoration: underline; } .article-content ul, .article-content ol { margin-left: 20px; margin-bottom: 1.2em; } .article-content li { margin-bottom: 0.8em; } .faq-list .question { font-weight: bold; color: var(–primary-color); margin-top: 1.5em; margin-bottom: 0.5em; display: block; } .faq-list .answer { margin-left: 10px; } .related-links ul { list-style: none; padding: 0; } .related-links li { margin-bottom: 1em; } .related-links a { font-weight: bold; } .related-links span { font-size: 0.9em; color: #666; display: block; margin-top: 5px; } .primary-highlight { background-color: var(–success-color); color: white; padding: 5px 10px; border-radius: 3px; font-weight: bold; display: inline-block; margin-left: 5px; }

401(k) Loan Calculator

Estimate your 401(k) loan repayment and understand its impact on your retirement savings.

401(k) Loan Details

Enter the amount you wish to borrow from your 401(k).
Typically between 1 to 5 years (12 to 60 months).
The interest rate charged by your 401(k) plan (often prime rate + 1-2%).
Your total vested balance before taking the loan.
Your estimated total annual contributions (employee + employer).
Your employer's matching contribution percentage.

Your Loan Summary

$0.00

Estimated Monthly Payment

Total Interest Paid

$0.00

Loan Repaid By

N/A

Remaining Balance (End of Loan)

$0.00
How it's calculated:

The monthly payment is calculated using the standard loan amortization formula: M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1]. The total interest is the sum of all monthly payments minus the principal loan amount. The impact on retirement growth is estimated by comparing the current balance growth with and without loan payments.

Assumptions: Interest rate remains constant, loan is repaid on schedule, and the estimated future contributions and growth rates are applied to the remaining balance.

Loan Amortization Schedule

Monthly breakdown of your 401(k) loan payments.
Period Payment Interest Paid Principal Paid Remaining Balance

Projected Retirement Growth Impact

Compares projected balance growth with and without the 401(k) loan payments, considering estimated future contributions and a hypothetical annual growth rate.

Key Assumptions

  • Loan Interest Rate: N/A% per year
  • Hypothetical Annual Investment Growth Rate: 7.0% (This is a hypothetical rate, actual returns will vary.)
  • Estimated Annual Contributions: $N/A
  • Employer Match: N/A% of contributions
  • Loan Repayment Term: N/A months

{primary_keyword}

A {primary_keyword} is a valuable tool that allows individuals to understand the financial implications of borrowing money from their own 401(k) retirement savings plan. It helps visualize how loan payments affect your take-home pay, the total interest you'll pay back, and, crucially, how it might hinder your retirement nest egg's growth. Understanding these factors is essential before deciding to take out a loan against your 401(k).

What is a 401(k) Loan?

A 401(k) loan allows eligible participants to borrow money from their 401(k) account. Unlike traditional loans, the money you borrow comes from your own retirement savings. You must repay the loan, typically with interest, back into your account. Employers often set limits on the loan amount (usually up to 50% of your vested balance or $50,000, whichever is less) and repayment terms, with most requiring repayment within five years, although loans for a primary residence may have longer terms. Crucially, the loan payments are made with after-tax dollars, but the interest paid back into your account is also credited after-tax, leading to potential double taxation upon withdrawal in retirement.

Who Should Use a 401(k) Loan Calculator?

Anyone considering taking a loan from their 401(k) should use a {primary_keyword}. This includes individuals facing short-term financial emergencies, such as:

  • Unexpected medical expenses
  • Urgent home repairs
  • Bridging a gap during job loss
  • Financing a major purchase when other options are unavailable

It's particularly important for those who want to understand the precise cost of the loan in terms of interest paid and the opportunity cost of lost investment growth. This tool helps make an informed decision, weighing the immediate need against long-term retirement security.

Common Misconceptions About 401(k) Loans

Several myths surround 401(k) loans. One common misconception is that borrowing from your 401(k) is "free money" because you're borrowing from yourself. While you do repay yourself, you incur interest costs and, more significantly, miss out on potential investment earnings that your money could have generated. Another myth is that it doesn't affect your retirement significantly. However, the loss of compounding growth on the borrowed amount and the interest paid can substantially reduce your final retirement balance. Additionally, some believe taking a loan is always better than a personal loan, but the tax implications and potential impact on investment growth make this comparison complex and dependent on individual circumstances.

{primary_keyword} Formula and Mathematical Explanation

The core of a {primary_keyword} lies in calculating the loan payments and projecting the financial impact. The primary calculation uses the standard loan amortization formula to determine the fixed monthly payment.

Loan Payment Formula

The formula for calculating the monthly loan payment (M) is:

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

Where:

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

Calculating Total Interest Paid

Once the monthly payment (M) is determined, the total interest paid over the life of the loan is calculated as:

Total Interest = (M * n) – P

Projected Retirement Impact

Estimating the impact on retirement growth involves projecting the future value of the current balance assuming it continues to grow with a hypothetical rate of return, and comparing it to the projected future value if the loan payments were instead invested. This involves compound interest calculations, factoring in the current balance, future contributions (including employer match), and the assumed annual growth rate, while accounting for the reduction in the invested balance due to loan repayments.

Variable Definitions Table

Variables Used in 401(k) Loan Calculations
Variable Meaning Unit Typical Range
P (Loan Amount) The principal amount borrowed from the 401(k) plan. Dollars ($) $1,000 – $50,000 (or 50% of vested balance)
i (Monthly Interest Rate) The interest rate applied to the loan on a monthly basis. Decimal (e.g., 0.05 / 12) 0.00333 – 0.01667 (for 4%-20% annual rates)
n (Loan Term) The total duration of the loan in months. Months 12 – 60 months (standard)
M (Monthly Payment) The fixed amount paid back to the 401(k) each month. Dollars ($) Calculated
Current Balance The total vested balance of the 401(k) prior to the loan. Dollars ($) $0+
Annual Contribution Total estimated employee and employer contributions per year. Dollars ($) $0+
Annual Growth Rate Hypothetical rate of return on investments. Percentage (%) 3% – 10% (highly variable)

Practical Examples (Real-World Use Cases)

Let's explore a couple of scenarios to illustrate how the {primary_keyword} works:

Example 1: Emergency Home Repair

Scenario: Sarah needs to borrow $10,000 from her 401(k) to fix a leaking roof. Her plan charges an annual interest rate of 6%, and the standard repayment term is 60 months. Her current 401(k) balance is $60,000, and she contributes $7,200 annually ($600/month) with a 3% employer match.

Inputs:

  • Loan Amount: $10,000
  • Loan Term: 60 months
  • Annual Interest Rate: 6.0%
  • Current 401(k) Balance: $60,000
  • Annual Contribution: $7,200
  • Employer Match: 3%

Calculated Results (using the calculator):

  • Estimated Monthly Payment: $193.33
  • Total Interest Paid: $1,599.80
  • Repayment End Date: 60 months from now
  • Remaining Balance (End of Loan): $0.00
  • Estimated Loss in Retirement Savings Growth (over 30 years, assuming 7% annual growth): ~$7,500

Interpretation: Sarah will pay back $11,599.80 over five years. While this addresses her immediate need, the calculator highlights the $1,599.80 in interest paid and, more significantly, the estimated ~$7,500 potential loss in future retirement growth due to the withdrawn funds and missed compounding. She needs to weigh this cost against the urgency of the repair.

Example 2: Bridging a Short Job Gap

Scenario: Mark is transitioning between jobs and needs $15,000 to cover living expenses for a few months. He has $80,000 in his 401(k) and his plan allows loans at 7.5% annual interest over 36 months. He plans to resume contributions immediately upon finding a new job, but for this calculation, we consider the balance without new contributions for the loan term.

Inputs:

  • Loan Amount: $15,000
  • Loan Term: 36 months
  • Annual Interest Rate: 7.5%
  • Current 401(k) Balance: $80,000
  • Annual Contribution: $0 (during job gap for simplicity)
  • Employer Match: 0% (during job gap)

Calculated Results (using the calculator):

  • Estimated Monthly Payment: $475.41
  • Total Interest Paid: $2,114.76
  • Repayment End Date: 36 months from now
  • Remaining Balance (End of Loan): $0.00
  • Estimated Loss in Retirement Savings Growth (over 25 years, assuming 7% annual growth): ~$10,000

Interpretation: Mark's loan will cost him $2,114.76 in interest over three years. The calculator also shows a significant projected loss in long-term retirement growth (~$10,000), emphasizing the opportunity cost. Mark must consider if the immediate liquidity is worth the long-term impact on his retirement savings and the potential tax implications if he cannot repay the loan promptly if he leaves his employer.

How to Use This {primary_keyword} Calculator

Using the {primary_keyword} is straightforward. Follow these steps to get a clear picture of your potential 401(k) loan:

Step-by-Step Instructions:

  1. Enter Loan Amount: Input the exact dollar amount you are considering borrowing. Check your plan's limits; typically, it's up to 50% of your vested balance or $50,000, whichever is less.
  2. Specify Loan Term: Enter the loan duration in months. Most plans require repayment within five years, but consult your plan documents.
  3. Input Annual Interest Rate: Find out the interest rate your 401(k) plan charges for loans. This is often based on the prime rate plus a small margin.
  4. Enter Current 401(k) Balance: Provide your total vested balance. This helps contextualize the loan amount relative to your retirement savings.
  5. Estimate Annual Contributions: Input your expected total annual contributions (employee deferrals plus employer match). This figure is used to estimate the potential loss in future growth.
  6. Enter Employer Match Rate: Specify your employer's matching contribution percentage.
  7. Click 'Calculate Loan': Once all fields are filled, press the button to see the results.

How to Read the Results:

  • Estimated Monthly Payment: This is the amount that will be deducted from your paycheck each pay period (or monthly, depending on your plan) to repay the loan. Ensure this fits comfortably within your budget.
  • Total Interest Paid: This shows the total dollar amount of interest you will pay back into your 401(k) over the loan's life. Remember, this interest is paid with after-tax dollars.
  • Repayment End Date: Indicates when the loan will be fully paid off.
  • Remaining Balance (End of Loan): This will typically be $0.00 for a standard loan calculation, indicating the loan principal has been fully repaid.
  • Projected Retirement Growth Impact: This crucial figure estimates how much less your retirement savings might be in the future due to taking the loan, considering missed investment earnings.
  • Amortization Schedule: Provides a detailed month-by-month breakdown of how each payment is allocated between principal and interest, and the declining balance.

Decision-Making Guidance:

Use the results to make an informed decision. Can you afford the monthly payment without straining your finances? Is the potential long-term loss in retirement savings justified by the immediate need for the funds? Consider alternatives like a home equity loan, personal loan, or line of credit, and compare their interest rates, fees, and repayment terms. Always prioritize your long-term retirement goals.

Key Factors That Affect {primary_keyword} Results

Several elements significantly influence the outcome of your 401(k) loan calculations and the overall impact on your finances and retirement:

  1. Loan Amount (Principal):

    The larger the loan amount, the higher the monthly payments and the total interest paid. It also means a larger portion of your retirement savings is temporarily removed from potential market growth.

  2. Loan Term (Duration):

    A longer loan term results in lower monthly payments but significantly increases the total interest paid and the duration your funds are unavailable for investment growth. A shorter term means higher monthly payments but less total interest and faster return of funds to your investment pool.

  3. Annual Interest Rate:

    A higher interest rate directly increases the monthly payment and the total interest paid. This rate is often dictated by your plan and market conditions (like the prime rate).

  4. Current 401(k) Balance:

    While not directly in the payment formula, a larger balance allows for a larger potential loan amount, but it also means the potential impact of lost growth on the borrowed portion is greater in absolute dollar terms, assuming the same growth rate.

  5. Opportunity Cost (Lost Investment Growth):

    This is arguably the most significant factor. The money borrowed is not invested and cannot grow through market appreciation or compounding. The longer the money is out, and the higher the market returns would have been, the greater this opportunity cost becomes, significantly impacting your final retirement balance.

  6. Future Contributions and Employer Match:

    While you're repaying the loan, your ability to contribute might be impacted by the loan payments. Furthermore, if your employer match is based on your contributions, a reduced contribution capacity could mean less free money from your employer. The calculator estimates the impact assuming continued contributions and match on the *remaining* balance.

  7. Tax Implications:

    Repayments are made with after-tax dollars. If you leave your job before repaying the loan, the outstanding balance is often treated as an early withdrawal, subject to income tax and a 10% penalty if you are under 59½. This adds a significant financial risk.

  8. Inflation:

    While not directly in the loan calculation, inflation erodes the purchasing power of money. The 'real' return on your 401(k) investments needs to outpace inflation. Borrowing potentially reduces your ability to achieve higher real returns, and the dollars you repay later might have less purchasing power.

Frequently Asked Questions (FAQ)

Can I borrow my entire 401(k) balance? No, typically you can only borrow up to 50% of your vested account balance or $50,000, whichever is less. Your specific plan documents will detail the exact limits. What happens if I leave my job while I have an outstanding 401(k) loan? This is a critical risk. Most plans require you to repay the outstanding loan balance within a short period (e.g., 60-90 days) after leaving employment. If you cannot repay it, the remaining balance is typically considered a taxable distribution, and you may owe income tax plus a 10% early withdrawal penalty if you're under age 59½. Is the interest I pay on a 401(k) loan tax-deductible? Generally, no. You repay the loan principal and interest with after-tax dollars. While the interest is paid back into your account, it is not tax-deductible for the borrower. However, the interest earned within the account grows tax-deferred until retirement withdrawal. How does a 401(k) loan affect my credit score? Taking a loan from your 401(k) generally does not affect your credit score because it is not typically reported to credit bureaus. However, defaulting on the loan (especially if it results in a deemed distribution) could lead to negative credit reporting. Should I prioritize a 401(k) loan over a personal loan or HELOC? It depends. 401(k) loans often have lower interest rates and easier approval than personal loans. However, they carry the significant risk of lost investment growth and potential penalties if you leave your job. Personal loans and HELOCs don't impact retirement funds directly but have different interest rates, fees, and credit score implications. Always compare the total costs and risks. How much can my 401(k) balance grow without the loan? The calculator provides an estimate of this potential growth. It compares the projected balance with the loan repayments versus the projected balance if the borrowed amount had remained invested and continued to compound over time, typically assuming a hypothetical annual rate of return. Are there fees associated with 401(k) loans? Some plans charge an origination fee to set up the loan and potentially an annual maintenance fee. These fees should be factored into your decision, although they are not always included in basic calculators. Check your plan details. What if I can't afford the monthly loan payments? If you anticipate difficulty making payments, it's crucial to reconsider taking the loan. Missing payments can lead to default, the loan balance becoming due immediately, and potential taxes and penalties. Explore alternatives or borrow a smaller amount if possible.

© 2023 Your Financial Company. All rights reserved.

This calculator is for informational purposes only and does not constitute financial advice. Consult with a qualified financial advisor before making any decisions.

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var interestRate = parseFloat(document.getElementById('interestRate').value); var currentBalance = parseFloat(document.getElementById('currentBalance').value); var annualContribution = parseFloat(document.getElementById('annualContribution').value); var employerMatchRate = parseFloat(document.getElementById('employerMatchRate').value); var allValid = true; if (!validateInput('loanAmount', 0, undefined, 'Loan Amount')) allValid = false; if (!validateInput('loanTermMonths', 1, undefined, 'Loan Term')) allValid = false; if (!validateInput('interestRate', 0, 20, 'Interest Rate')) allValid = false; if (!validateInput('currentBalance', 0, undefined, 'Current 401(k) Balance')) allValid = false; if (!validateInput('annualContribution', 0, undefined, 'Annual Contribution')) allValid = false; if (!validateInput('employerMatchRate', 0, 10, 'Employer Match Rate')) allValid = false; // Additional check for loan amount vs balance if (loanAmount > currentBalance * 0.5) { document.getElementById('loanAmountError').textContent = 'Loan amount cannot exceed 50% of your current balance.'; allValid = false; } if (loanAmount > 50000) { document.getElementById('loanAmountError').textContent = 'Loan amount cannot exceed $50,000.'; allValid = false; } if (!allValid) { document.getElementById('results-section').style.display = 'none'; return; } var monthlyInterestRate = interestRate / 100 / 12; var numPayments = loanTermMonths; // Calculate Monthly Payment (M) var monthlyPayment = 0; if (monthlyInterestRate > 0) { monthlyPayment = loanAmount * (monthlyInterestRate * Math.pow(1 + monthlyInterestRate, numPayments)) / (Math.pow(1 + monthlyInterestRate, numPayments) – 1); } else { monthlyPayment = loanAmount / numPayments; // Simple division if rate is 0 } // Calculate Total Interest Paid var totalInterestPaid = (monthlyPayment * numPayments) – loanAmount; // Calculate Remaining Balance at end of loan (should be 0 if calculated correctly) var remainingBalanceEnd = loanAmount; for (var i = 0; i < numPayments; i++) { var interestForMonth = remainingBalanceEnd * monthlyInterestRate; var principalForMonth = monthlyPayment – interestForMonth; remainingBalanceEnd -= principalForMonth; if (remainingBalanceEnd < 0.01) remainingBalanceEnd = 0; // Handle potential floating point inaccuracies } document.getElementById('primaryResult').textContent = formatCurrency(monthlyPayment); document.getElementById('totalInterest').textContent = formatCurrency(totalInterestPaid); document.getElementById('repaymentEndDate').textContent = numPayments + ' Months'; document.getElementById('remainingBalance').textContent = formatCurrency(remainingBalanceEnd); document.getElementById('assumpRate').textContent = interestRate.toFixed(2); document.getElementById('assumpContributions').textContent = annualContribution.toFixed(2); document.getElementById('assumpTerm').textContent = loanTermMonths; var employerMatchAmount = (annualContribution * employerMatchRate / 100); document.getElementById('assumpMatch').textContent = employerMatchRate.toFixed(1); // Populate Amortization Table var amortizationBody = document.getElementById('amortizationBody'); amortizationBody.innerHTML = ''; // Clear previous data var currentBalanceAmort = loanAmount; var amortizationData = []; for (var i = 1; i <= numPayments; i++) { var interestPayment = currentBalanceAmort * monthlyInterestRate; var principalPayment = monthlyPayment – interestPayment; currentBalanceAmort -= principalPayment; if (currentBalanceAmort < 0.01) { // Ensure balance doesn't go negative due to float precision principalPayment = principalPayment + currentBalanceAmort; // Adjust last principal payment interestPayment = monthlyPayment – principalPayment; currentBalanceAmort = 0; } if (principalPayment < 0) principalPayment = 0; // Ensure no negative principal if (interestPayment < 0) interestPayment = 0; // Ensure no negative interest amortizationData.push({ period: i, payment: monthlyPayment, interest: interestPayment, principal: principalPayment, balance: currentBalanceAmort }); var row = amortizationBody.insertRow(); row.insertCell(0).textContent = i; row.insertCell(1).textContent = formatCurrency(monthlyPayment); row.insertCell(2).textContent = formatCurrency(interestPayment); row.insertCell(3).textContent = formatCurrency(principalPayment); row.insertCell(4).textContent = formatCurrency(currentBalanceAmort); } // Update Chart updateGrowthChart(currentBalance, annualContribution, employerMatchRate, loanAmount, monthlyPayment, loanTermMonths); document.getElementById('results-section').style.display = 'block'; } function updateGrowthChart(initialBalance, annualContribution, employerMatchRate, loanAmount, monthlyPayment, loanTermMonths) { var growthChartCanvas = document.getElementById('growthChart'); if (!growthChartCanvas) return; var ctx = growthChartCanvas.getContext('2d'); // Clear previous chart if it exists if (chartInstance) { chartInstance.destroy(); } var futureYears = 30; // Project for 30 years var annualGrowthRate = 0.07; // Hypothetical 7% annual growth rate var contributionPerMonth = annualContribution / 12; var employerMatchPerMonth = (annualContribution * employerMatchRate / 100) / 12; var loanRepaymentPerMonth = monthlyPayment; var loanTermYears = loanTermMonths / 12; var balanceWithLoan = []; var balanceWithoutLoan = []; var labels = []; var currentBalanceWithLoan = initialBalance; var currentBalanceWithoutLoan = initialBalance; var monthsPassed = 0; for (var year = 0; year 0) { // Start contributions after first year for simplicity in annual projection var contributionsThisYear = (annualContribution + (annualContribution * employerMatchRate / 100)); currentBalanceWithoutLoan = currentBalanceWithoutLoan * (1 + annualGrowthRate) + contributionsThisYear; } balanceWithoutLoan.push(currentBalanceWithoutLoan); // With Loan Calculation // First, account for loan payments during the loan term if (monthsPassed < loanTermMonths) { var interestOnLoanPayment = (currentBalanceWithLoan – loanAmount) * monthlyInterestRate; // Simplified interest calculation for chart context, not loan payment itself var principalPaymentForChart = loanRepaymentPerMonth – interestOnLoanPayment; // Simplified principal repayment for chart context if (principalPaymentForChart loanAmount) { // Deduct loan principal from available balance currentBalanceWithLoan -= principalPaymentForChart; } else { // If balance drops below loan principal, assume loan repayment comes from remaining balance first currentBalanceWithLoan = loanAmount – principalPaymentForChart; if (currentBalanceWithLoan < 0) currentBalanceWithLoan = 0; } currentBalanceWithLoan += (annualContribution + (annualContribution * employerMatchRate / 100)); // Add contributions currentBalanceWithLoan *= (1 + annualGrowthRate); // Apply growth monthsPassed++; } else { // After loan is paid off, add back the loan amount (minus interest paid) and continue growth // Re-adding principal here is a simplification. A more accurate model would track remaining investment value precisely. // For simplicity, assume loan is paid off and contributions resume normally, minus the earlier principal deduction. // The key impact is the lost growth on the borrowed funds *during* the loan term. // We assume loan repayment is fully completed. var contributionsThisYear = (annualContribution + (annualContribution * employerMatchRate / 100)); currentBalanceWithLoan = currentBalanceWithLoan * (1 + annualGrowthRate) + contributionsThisYear; } balanceWithLoan.push(currentBalanceWithLoan); } // Recalculate Without Loan for accurate comparison: var projectedBalanceWithoutLoan = initialBalance; for(var i = 0; i < futureYears; i++) { var contributionsForYear = annualContribution + (annualContribution * employerMatchRate / 100); projectedBalanceWithoutLoan = projectedBalanceWithoutLoan * (1 + annualGrowthRate) + contributionsForYear; // Ensure balance doesn't dip below zero if growth/contributions are negative if (projectedBalanceWithoutLoan < 0) projectedBalanceWithoutLoan = 0; balanceWithoutLoan[i] = projectedBalanceWithoutLoan; } // Recalculate With Loan for accurate comparison: var projectedBalanceWithLoan = initialBalance; var currentLoanBalance = loanAmount; var totalInterestPaidChart = 0; var monthlyInterestRateChart = (document.getElementById('interestRate').value / 100) / 12; var numPaymentsChart = document.getElementById('loanTermMonths').value; var monthlyPaymentChart = parseFloat(document.getElementById('primaryResult').textContent.replace(/[^0-9.-]+/g,"")); // Get calculated monthly payment for (var i = 0; i < futureYears * 12; i++) { // Iterate month by month for accuracy // Account for loan repayment if within term if (i < numPaymentsChart) { var interestPaymentChart = currentLoanBalance * monthlyInterestRateChart; var principalPaymentChart = monthlyPaymentChart – interestPaymentChart; if (principalPaymentChart < 0) principalPaymentChart = 0; // Safety check if (interestPaymentChart < 0) interestPaymentChart = 0; // Safety check currentLoanBalance -= principalPaymentChart; if (currentLoanBalance < 0.01) { currentLoanBalance = 0; // If loan paid off early in the month, adjust remaining payment for that month monthlyPaymentChart = interestPaymentChart + principalPaymentChart; } totalInterestPaidChart += interestPaymentChart; projectedBalanceWithLoan -= principalPaymentChart; // Deduct principal payment from total balance } // Add contributions (assuming they happen monthly) projectedBalanceWithLoan += (annualContribution / 12) + ((annualContribution * employerMatchRate / 100) / 12); // Apply monthly growth projectedBalanceWithLoan *= (1 + (annualGrowthRate / 12)); // Ensure balance doesn't dip below zero if (projectedBalanceWithLoan < 0) projectedBalanceWithLoan = 0; // Store yearly values for the chart if ((i + 1) % 12 === 0) { var yearIndex = (i + 1) / 12; labels.push(yearIndex); balanceWithLoan.push(projectedBalanceWithLoan); // Calculate balanceWithoutLoan for this specific year using same logic var projectedBalanceWithoutLoanYear = initialBalance; for(var j=0; j < yearIndex; j++){ var contributionsForYear = annualContribution + (annualContribution * employerMatchRate / 100); projectedBalanceWithoutLoanYear = projectedBalanceWithoutLoanYear * (1 + annualGrowthRate) + contributionsForYear; if (projectedBalanceWithoutLoanYear labels.length) { balanceWithoutLoan = balanceWithoutLoan.slice(0, labels.length); } else { while(balanceWithoutLoan.length labels.length) { balanceWithLoan = balanceWithLoan.slice(0, labels.length); } else { while(balanceWithLoan.length = 1000) { return '$' + (value / 1000).toFixed(0) + 'K'; } else if (value > 0) { return '$' + value.toFixed(0); } return "; } } }, x: { title: { display: true, text: 'Years from Now' } } }, plugins: { tooltip: { callbacks: { label: function(context) { var label = context.dataset.label || "; if (label) { label += ': '; } if (context.parsed.y !== null) { label += formatCurrency(context.parsed.y); } return label; } } } } } }); } function resetCalculator() { document.getElementById('loanAmount').value = '10000'; document.getElementById('loanTermMonths').value = '60'; document.getElementById('interestRate').value = '5.0'; document.getElementById('currentBalance').value = '50000'; document.getElementById('annualContribution').value = '5000'; document.getElementById('employerMatchRate').value = '3'; // Clear errors document.getElementById('loanAmountError').textContent = "; document.getElementById('loanTermMonthsError').textContent = "; document.getElementById('interestRateError').textContent = "; document.getElementById('currentBalanceError').textContent = "; document.getElementById('annualContributionError').textContent = "; document.getElementById('employerMatchRateError').textContent = "; document.getElementById('validation-message').textContent = "; document.getElementById('results-section').style.display = 'none'; } function copyResults() { var monthlyPayment = document.getElementById('primaryResult').textContent; var totalInterest = document.getElementById('totalInterest').textContent; var repaymentEndDate = document.getElementById('repaymentEndDate').textContent; var remainingBalance = document.getElementById('remainingBalance').textContent; var loanAmount = formatCurrency(parseFloat(document.getElementById('loanAmount').value)); var loanTermMonths = document.getElementById('loanTermMonths').value + ' Months'; var interestRate = document.getElementById('interestRate').value + '%'; var currentBalance = formatCurrency(parseFloat(document.getElementById('currentBalance').value)); var annualContribution = formatCurrency(parseFloat(document.getElementById('annualContribution').value)); var employerMatchRate = document.getElementById('employerMatchRate').value + '%'; var assumptions = "Key Assumptions:\n"; assumptions += "- Loan Interest Rate: " + document.getElementById('assumpRate').textContent + "%\n"; assumptions += "- Estimated Annual Contributions: " + formatCurrency(parseFloat(document.getElementById('annualContribution').value)) + "\n"; assumptions += "- Employer Match: " + document.getElementById('assumpMatch').textContent + "%\n"; assumptions += "- Loan Repayment Term: " + document.getElementById('assumpTerm').textContent + " months\n"; assumptions += "- Hypothetical Annual Investment Growth Rate: 7.0%\n"; // Hardcoded as per chart var textToCopy = "— 401(k) Loan Calculation Results —\n\n"; textToCopy += "Loan Details:\n"; textToCopy += "- Loan Amount: " + loanAmount + "\n"; textToCopy += "- Loan Term: " + loanTermMonths + "\n"; textToCopy += "- Annual Interest Rate: " + interestRate + "\n"; textToCopy += "- Current 401(k) Balance: " + currentBalance + "\n"; textToCopy += "- Annual Contribution: " + annualContribution + "\n"; textToCopy += "- Employer Match Rate: " + employerMatchRate + "\n\n"; textToCopy += "Summary:\n"; textToCopy += "- Estimated Monthly Payment: " + monthlyPayment + "\n"; textToCopy += "- Total Interest Paid: " + totalInterest + "\n"; textToCopy += "- Repayment End Date: " + repaymentEndDate + "\n"; textToCopy += "- Remaining Balance (End of Loan): " + remainingBalance + "\n\n"; textToCopy += assumptions; // Use navigator.clipboard for modern browsers, fallback to prompt/textarea for older ones if (navigator.clipboard && navigator.clipboard.writeText) { navigator.clipboard.writeText(textToCopy).then(function() { alert('Results copied to clipboard!'); }).catch(function(err) { console.error('Could not copy text: ', err); fallbackCopyTextToClipboard(textToCopy); }); } else { fallbackCopyTextToClipboard(textToCopy); } } function fallbackCopyTextToClipboard(text) { var textArea = document.createElement("textarea"); textArea.value = text; textArea.style.position = "fixed"; // Avoid scrolling to bottom textArea.style.left = "-9999px"; textArea.style.top = "-9999px"; document.body.appendChild(textArea); textArea.focus(); textArea.select(); try { var successful = document.execCommand('copy'); var msg = successful ? 'successful' : 'unsuccessful'; alert('Results copied to clipboard! (' + msg + ')'); } catch (err) { console.error('Fallback: Oops, unable to copy', err); alert('Could not copy text. Please manually copy the results.'); } document.body.removeChild(textArea); } // Add Chart.js library dynamically if not present (for older browsers compatibility if needed) // For this standalone HTML, we assume Chart.js might not be present and add it. // In a real WP setup, you'd enqueue it properly. if (typeof Chart === 'undefined') { var script = document.createElement('script'); script.src = 'https://cdn.jsdelivr.net/npm/chart.js@3.7.0/dist/chart.min.js'; script.onload = function() { console.log('Chart.js loaded.'); // If calculator has already been rendered, update chart after library load if (document.getElementById('results-section').style.display === 'block') { calculateLoan(); // Re-run calculation to update chart } }; script.onerror = function() { console.error('Failed to load Chart.js.'); alert('Error loading charting library. Charts may not display.'); }; document.head.appendChild(script); } else { // If Chart.js is already available, ensure chart updates if needed on load // This might happen if the script runs before DOM is fully ready, or if results are already visible. window.addEventListener('load', function() { if (document.getElementById('results-section').style.display === 'block') { calculateLoan(); } }); } // Initial calculation on page load if defaults are set and results section is visible (which it isn't by default) window.addEventListener('load', function() { // Optionally trigger calculateLoan() here if you want defaults calculated on load. // calculateLoan(); });

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