Loan Amortization Schedule

What an amortization schedule shows

An amortization schedule is the month-by-month breakdown of a fixed-rate loan: for every payment, how much goes to interest, how much pays down the balance (principal), and what's left to owe. Early on, most of each payment is interest; over time the balance shrinks and more of each payment goes to principal. This tool builds the full schedule, draws the payoff curve, and lets you download the whole table as a CSV — all in your browser.

How the payment is calculated

The fixed monthly payment comes from the standard amortization formula, using the loan amount, the monthly interest rate (annual rate ÷ 12), and the number of payments (years × 12). Each month we charge interest on the remaining balance, subtract the rest of the payment from the principal, and carry the new balance forward — repeating until the loan reaches zero.

The power of extra payments

Add an extra monthly payment and the schedule recalculates: every extra peso or dollar goes straight to principal, so the balance falls faster, you pay off the loan sooner, and you pay less total interest. The "interest saved" and "payoff time" figures show exactly how much a little extra each month is worth. On a long mortgage, even a small extra payment can save years and a large amount of interest — something that's hard to see without a full schedule.

The chart and the CSV

The curve plots your remaining balance over the life of the loan, so you can see how slowly it drops at first and how it accelerates later (and how much extra payments steepen it). The Download CSV button gives you the complete schedule — every month's payment, principal, interest, and balance — to open in Excel, Google Sheets, or Numbers.

Notes & limitations

This models a fixed-rate, fully amortizing loan. It doesn't include taxes, insurance, PMI, fees, or a variable rate, and it assumes payments are made on schedule. For a real loan, use your lender's figures and APR. It's an estimate to help you plan, not a statement from your bank.

FAQ

Why is so much of my early payment interest?

Interest is charged on the outstanding balance, which is highest at the start. As the balance falls, the interest portion shrinks and the principal portion grows — that crossover is exactly what the schedule reveals.

Just need the monthly payment?

Use the simpler loan payment calculator.

Is this amortization tool free, and does my loan data stay private?

Yes, it's completely free with no sign-up. Every calculation runs in your browser, so the loan amount, rate, and term you enter are never sent to a server or stored anywhere. You can even use it offline once the page has loaded.

Why does my payment differ slightly from my lender's statement?

This tool models a clean fixed-rate loan using the nominal annual rate divided by 12. Lenders may round payments to the nearest cent, use a daily interest method, or fold in escrow for taxes and insurance, which shifts the numbers a little. Treat the schedule as a close planning estimate rather than an exact match to your statement.

How much interest can extra payments really save?

It depends on your rate and how early you start, but on a 30-year mortgage even an extra payment of a few percent of the regular amount can cut years off the term and save a large share of total interest. Enter your figures in the extra-payment box and the "interest saved" and "payoff time" numbers show the exact impact for your loan.

Can I open the downloaded schedule in Excel or Google Sheets?

Yes. The Download CSV button produces a standard comma-separated file with a row for every payment, which opens directly in Excel, Google Sheets, Numbers, or any spreadsheet app for further analysis or printing.