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Amortization Schedule Calculator
Generate the complete payment-by-payment schedule for any fixed-rate loan — mortgage, auto, personal, or student loan. See exactly how much of each payment goes to principal vs. interest, and download the full table as a CSV file.
Loan Details
What is an amortization schedule?
An amortization schedule is a table that breaks down every single payment of a loan over its full term, showing exactly how much of that payment goes toward interest versus principal, and what the remaining balance is after each payment. For a fixed-rate loan, the total payment stays the same every period, but the split between principal and interest shifts over time: early payments are interest-heavy (because the balance — and the interest it accrues — is highest at the start), while later payments are principal-heavy.
How the schedule is generated
Each row is calculated using the standard amortization formula. First, the fixed monthly payment is found using M = P × [ r(1+r)n ] / [ (1+r)n − 1 ], where P is the loan amount, r is the monthly interest rate, and n is the total number of payments. Then, for each payment: interest = current balance × monthly rate; principal = payment − interest; new balance = old balance − principal (plus any extra payment you specify, which comes entirely off principal).
Frequently asked questions
Can I use this for a mortgage, car loan, or student loan?
Yes — the amortization math is identical for any fixed-rate, fixed-term loan. For a mortgage specifically with taxes, insurance, and PMI included in the monthly payment, use the mortgage calculator instead; this page focuses purely on the principal-and-interest schedule.
Can I download the full schedule?
Yes. Click "Download CSV" after generating a schedule to save the complete payment-by-payment table as a spreadsheet file you can open in Excel, Google Sheets, or Numbers.
What if I add extra payments?
Enter an "Extra payment per month" amount and the schedule will apply that extra amount directly to principal every period, shortening the loan and reducing total interest. To see a full side-by-side comparison of standard vs. extra-payment payoff, use the loan payoff calculator.
Is my loan data uploaded anywhere?
No. The entire schedule is generated and displayed locally in your browser using JavaScript, and the CSV file is created and downloaded directly from your browser — nothing is sent to a server.