Student Loan Monthly Payment Calculator

ANALife Services AuthorityNational Calculator Authority›Student Loan Monthly Payment Calculator

.calc-container { max-width: 640px; margin: 2rem 0; padding: 1.5rem; background: #fff; border: 1px solid #ddd; border-radius: 8px; box-shadow: 0 1px 3px rgba(0,0,0,0.06); font-family: system-ui, -apple-system, sans-serif; } .calc-container h3 { font-family: Georgia, serif; font-size: 1.15rem; color: #1a1a1a; margin-bottom: 1rem; padding-bottom: 0.5rem; border-bottom: 2px solid var(--ac, #3d5a80); } .calc-row { display: flex; align-items: center; gap: 0.75rem; margin-bottom: 0.75rem; flex-wrap: wrap; } .calc-row label { min-width: 160px; font-size: 0.9rem; color: #333; font-weight: 500; } .calc-row input[type="number"], .calc-row select { flex: 1; min-width: 120px; max-width: 200px; padding: 0.5rem 0.6rem; border: 1px solid #ccc; border-radius: 4px; font-size: 0.9rem; font-family: system-ui, sans-serif; color: #1a1a1a; background: #fafaf8; } .calc-row input:focus, .calc-row select:focus { outline: none; border-color: var(--ac, #3d5a80); box-shadow: 0 0 0 2px rgba(26,74,138,0.12); } .calc-row .unit { font-size: 0.82rem; color: #888; min-width: 30px; } .calc-btn { display: inline-block; margin-top: 0.5rem; padding: 0.55rem 1.5rem; background: var(--ac, #3d5a80); color: #fff; border: none; border-radius: 4px; font-size: 0.9rem; font-weight: 600; cursor: pointer; font-family: system-ui, sans-serif; } .calc-btn:hover { opacity: 0.9; } .calc-result { margin-top: 1.25rem; padding: 1rem 1.25rem; background: #f0f6fc; border-left: 3px solid var(--ac, #3d5a80); border-radius: 0 6px 6px 0; display: none; } .calc-result.visible { display: block; } .calc-result-label { font-size: 0.78rem; text-transform: uppercase; letter-spacing: 0.06em; color: #666; margin-bottom: 0.25rem; } .calc-result-value { font-size: 1.6rem; font-weight: 700; color: var(--ac, #3d5a80); } .calc-result-detail { font-size: 0.85rem; color: #555; margin-top: 0.5rem; line-height: 1.5; } .calc-note { margin-top: 1rem; font-size: 0.8rem; color: #888; font-style: italic; } .calc-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 0.75rem; margin-top: 0.75rem; } .calc-grid-item { padding: 0.6rem 0.8rem; background: #f8f9fa; border-radius: 4px; border: 1px solid #eee; } .calc-grid-item .label { font-size: 0.75rem; color: #888; text-transform: uppercase; letter-spacing: 0.04em; } .calc-grid-item .value { font-size: 1.1rem; font-weight: 600; color: #1a1a1a; } @media (max-width: 720px) { .calc-row { flex-direction: column; align-items: flex-start; gap: 0.3rem; } .calc-row label { min-width: auto; } .calc-row input[type="number"], .calc-row select { max-width: 100%; width: 100%; } .calc-grid { grid-template-columns: 1fr; } } .calc-chart { margin: 1rem 0; text-align: center; } .calc-chart svg { max-width: 100%; height: auto; } .calc-chart-legend { display: flex; flex-wrap: wrap; justify-content: center; gap: 0.6rem 1.2rem; margin-top: 0.6rem; font-size: 0.8rem; color: #555; } .calc-chart-legend span { display: inline-flex; align-items: center; gap: 0.3rem; } .calc-chart-legend i { display: inline-block; width: 10px; height: 10px; border-radius: 2px; font-style: normal; } .calc-related { max-width: 640px; margin: 2rem 0 1rem; padding: 1.25rem 1.5rem; background: #f8f9fa; border: 1px solid #e8e8e8; border-radius: 8px; } .calc-related h3 { font-family: Georgia, serif; font-size: 1rem; color: #1a1a1a; margin: 0 0 0.75rem; padding-bottom: 0.4rem; border-bottom: 2px solid var(--ac, #3d5a80); } .calc-related-list { list-style: none; padding: 0; margin: 0 0 0.75rem; display: grid; grid-template-columns: 1fr 1fr; gap: 0.4rem 1.5rem; } .calc-related-list li a { font-size: 0.88rem; color: var(--ac, #3d5a80); text-decoration: none; } .calc-related-list li a:hover { text-decoration: underline; } .calc-browse-all { margin: 0.5rem 0 0; font-size: 0.9rem; font-weight: 600; } .calc-browse-all a { color: var(--ac, #3d5a80); text-decoration: none; } .calc-browse-all a:hover { text-decoration: underline; } @media (max-width: 720px) { .calc-related-list { grid-template-columns: 1fr; } }

Student Loan Monthly Payment Calculator

Estimate your monthly student loan payment using the standard amortization formula. Enter your loan details below to see your required monthly payment, total amount paid, and total interest paid over the life of the loan.

Loan Amount ($)

Annual Interest Rate (%)

Repayment Term (Years)

Extra Monthly Payment ($) (optional)

Calculate

function stuCalc() { var resultDiv = document.getElementById('stu-result'); resultDiv.style.display = 'none'; resultDiv.innerHTML = '';

var principal = parseFloat(document.getElementById('stu-principal').value); var annualRate = parseFloat(document.getElementById('stu-rate').value); var termYears = parseFloat(document.getElementById('stu-term').value); var extra = parseFloat(document.getElementById('stu-extra').value) || 0;

// --- Input Validation --- var errors = []; if (isNaN(principal) || principal 1000000) { errors.push('Loan Amount must be between $100 and $1,000,000.'); } if (isNaN(annualRate) || annualRate 30) { errors.push('Annual Interest Rate must be between 0% and 30%.'); } if (isNaN(termYears) || termYears 30 || !Number.isInteger(termYears)) { errors.push('Repayment Term must be a whole number between 1 and 30 years.'); } if (isNaN(extra) || extra 100000) { errors.push('Extra Monthly Payment must be between $0 and $100,000.'); } if (errors.length > 0) { resultDiv.style.display = 'block'; resultDiv.innerHTML = '' + errors.map(function(e){ return ''; }).join('') + ''; return; }

var monthlyRate = annualRate / 100 / 12; var n = termYears * 12; // total number of payments

// --- Standard Amortization Formula --- // M = P * [r(1+r)^n] / [(1+r)^n - 1] // Special case: if rate = 0, M = P / n var monthlyPayment; if (monthlyRate === 0) { monthlyPayment = principal / n; } else { var factor = Math.pow(1 + monthlyRate, n); monthlyPayment = principal * (monthlyRate * factor) / (factor - 1); }

var totalPayment = monthlyPayment * n; var totalInterest = totalPayment - principal;

// --- Extra Payment Simulation --- var extraMonthlyPayment = monthlyPayment + extra; var extraTotalPaid = 0; var extraTotalInterest = 0; var extraMonthsCount = 0; var balance = principal;

if (extra > 0) { while (balance > 0 && extraMonthsCount balance) { // Final payment var finalPayment = balance + interestCharge; extraTotalPaid += finalPayment; extraTotalInterest += interestCharge; balance = 0; extraMonthsCount++; break; } balance -= principalPayment; extraTotalPaid += extraMonthlyPayment; extraTotalInterest += interestCharge; extraMonthsCount++; } }

// --- Format helpers --- function fmt(val) { return val.toLocaleString('en-US', { style: 'currency', currency: 'USD', minimumFractionDigits: 2, maximumFractionDigits: 2 }); } function fmtYM(months) { var y = Math.floor(months / 12); var m = months % 12; var parts = []; if (y > 0) parts.push(y + ' yr' + (y !== 1 ? 's' : '')); if (m > 0) parts.push(m + ' mo' + (m !== 1 ? 's' : '')); return parts.join(' '); }

// --- Build Result HTML --- var html = '### Results '; html += ''; html += 'Monthly Payment' + fmt(monthlyPayment) + ''; html += 'Total Amount Paid' + fmt(totalPayment) + ''; html += 'Total Interest Paid' + fmt(totalInterest) + ''; html += 'Repayment Period' + fmtYM(n) + ''; html += '';

if (extra > 0 && extraMonthsCount > 0) { var timeSaved = n - extraMonthsCount; var interestSaved = totalInterest - extraTotalInterest; html += '### With Extra Payment of ' + fmt(extra) + '/mo '; html += ''; html += 'New Monthly Payment' + fmt(extraMonthlyPayment) + ''; html += 'Total Amount Paid' + fmt(extraTotalPaid) + ''; html += 'Total Interest Paid' + fmt(extraTotalInterest) + ''; html += 'New Repayment Period' + fmtYM(extraMonthsCount) + ''; html += 'Time Saved' + fmtYM(timeSaved) + ''; html += 'Interest Saved' + fmt(interestSaved) + ''; html += ''; } else if (extra > 0 && extraMonthsCount === -1) { html += 'Extra payment scenario could not be computed — the payment may not cover monthly interest.

'; }

resultDiv.innerHTML = html; resultDiv.style.display = 'block'; }

#### Formula

The standard loan amortization formula is used to calculate the fixed monthly payment:

M = P × [r(1 + r)n] / [(1 + r)n − 1]

If the annual interest rate is 0%, the formula simplifies to: M = P / n

Total Amount Paid = M × n

Total Interest Paid = Total Amount Paid − P

When an extra monthly payment is added, the payoff timeline is simulated month-by-month, reducing the principal faster and shortening the loan term.

#### Assumptions & References

More Calculators

References


The law belongs to the people. Georgia v. Public.Resource.Org, 590 U.S. (2020)