15 Year Amortization Calculator

This 15-year amortization calculator helps you determine monthly loan payments, total interest paid, and the amortization schedule for a 15-year loan term. Whether you're evaluating a mortgage, auto loan, or personal loan, this tool provides clear insights into your repayment plan.

What is Amortization?

Amortization is the process of paying off a loan through scheduled, regular payments that cover both the loan's interest and principal. Each payment reduces the outstanding loan balance, making it a systematic way to repay debt over time.

For a 15-year loan, amortization schedules typically show how much of each payment goes toward interest and how much goes toward the principal. This helps borrowers understand their repayment strategy and plan their finances accordingly.

How to Use This Calculator

Enter the loan amount you're considering.
Input the annual interest rate (APR).
Select the loan term (15 years in this case).
Click "Calculate" to see your monthly payment, total interest, and amortization schedule.
Review the results and adjust your inputs as needed.

Note: This calculator assumes monthly compounding and does not account for prepayment penalties or changes in interest rates.

Formula Used

The monthly payment (PMT) for an amortized loan is calculated using the following formula:

PMT = P × [r(1 + r)^n] / [(1 + r)^n - 1]

Where:

P = Principal loan amount
r = Monthly interest rate (annual rate ÷ 12)
n = Number of payments (loan term in years × 12)

Total interest paid is calculated by multiplying the monthly payment by the total number of payments and subtracting the principal loan amount.

Worked Example

Let's calculate a 15-year amortization schedule for a $100,000 loan at a 4.5% annual interest rate.

Convert the annual rate to monthly: 4.5% ÷ 12 = 0.375% or 0.00375 in decimal.
Calculate the number of payments: 15 years × 12 = 180 payments.
Plug values into the formula:

PMT = $100,000 × [0.00375(1 + 0.00375)^180] / [(1 + 0.00375)^180 - 1]

PMT ≈ $743.65 per month
Total interest paid: ($743.65 × 180) - $100,000 ≈ $63,254.00

This example shows that over 15 years, you would pay approximately $743.65 per month, with $63,254.00 going toward interest.

Frequently Asked Questions

What is the difference between amortization and interest-only payments?

Amortization involves paying both principal and interest each month, gradually reducing the loan balance. Interest-only payments only cover the interest, leaving the principal unchanged until the end of the loan term.

How does a longer loan term affect my monthly payments?

A longer loan term typically results in lower monthly payments but higher total interest costs. Conversely, a shorter term usually means higher monthly payments but lower total interest.

Can I prepay my loan without penalties?

Prepayment policies vary by lender. Some loans allow prepayment without penalties, while others may charge fees. Always check your loan agreement or contact your lender for specific terms.