Mortgage Amortization Calculator
Generate a complete mortgage amortization schedule showing the payment distribution of principal and interest over the loan term.
Calculation Results
Estimated monthly payment covering principal and interest.
The sum of all monthly mortgage payments over the life of the loan.
Total interest paid to the lender over the loan term.
Amortization Schedule
Year-by-year breakdown of your payments, interest, and remaining balance.
| Year | Beginning Balance | Principal Paid | Interest Paid | Total Paid | Ending Balance |
|---|
How This Calculator Works
To generate your mortgage amortization schedule:
- Enter the total mortgage loan amount (excluding down payment).
- Provide the interest rate and the loan term (e.g. 30 or 15 years).
The calculator returns your monthly P&I payment, total interest cost, and generates a yearly table tracking the principal reduction and interest amortization.
Formula & Calculations
The monthly principal and interest payment is calculated using standard amortization:
Monthly Payment = Loan Amount × [ r(1 + r)^n ] / [ (1 + r)^n - 1 ]
Where r = interest_rate / 12 / 100 and n = loan_term × 12.
The total payment represents the monthly payment made over the lifetime of the mortgage loan:
Total Cost = Monthly Payment × n
The total interest paid is the total cost minus the original borrowed amount:
Total Interest = Total Cost - Loan Amount
Step-by-Step Calculation Examples
Standard $300,000 Loan
Amortization breakdown for a conventional 30-year fixed loan of $300,000 at 6.5% interest.
- loan_amount: 300000
- interest_rate: 6.5
- loan_term: 30
- monthly_payment: $1,896.20
- total_payment: $682,633.47
- total_interest: $382,633.47
Frequently Asked Questions
What is mortgage amortization?
Amortization is the process of spreading out a loan into a series of equal periodic payments. Although each monthly payment is equal, the ratio of principal to interest shifts: early payments go mostly to interest, whereas later payments go mostly to principal.
How do extra payments affect the amortization schedule?
Any extra payment made goes 100% to pay down your principal balance. This reduces the outstanding balance, meaning less interest is charged in each subsequent month, shortening your loan term and saving interest.
Can I download the amortization table?
Yes. Below the generated schedule, click the "Export CSV" button to download a spreadsheet copy of your yearly breakdown.