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Generate a full month-by-month amortization schedule for any loan: your monthly payment, and exactly how much of each payment goes to principal versus interest, all the way to payoff. Add an extra monthly payment to see how much time and interest it saves, and download the full schedule as a CSV file for Excel.
Balance over time
Amortization schedule
| # | Date | Payment | Principal | Interest | Balance |
|---|
How an amortization schedule works
Every payment on a fixed-rate loan is split between interest and principal. Early in the loan, most of each payment is interest, because interest is calculated on the full remaining balance. As the balance goes down, less of each payment is needed for interest, so more goes toward principal — the payment amount stays the same, but its makeup shifts over time. A full amortization schedule shows that split for every single payment, from the first to the last.
The amortization formula
- Monthly payment = principal × monthly rate ÷ (1 − (1 + monthly rate)^−number of payments)
- Monthly rate = annual interest rate ÷ 12 ÷ 100
- Interest portion of a payment = remaining balance × monthly rate
- Principal portion of a payment = payment − interest portion
When the interest rate is 0%, the formula simplifies to the loan amount divided evenly by the number of payments, since there's no interest to split out.
Worked example
A $200,000 loan at 6% annual interest over 30 years (360 monthly payments): the monthly payment is about $1,199.10. In the very first payment, around $1,000 of that is interest and only about $199 goes to principal. By the final payments, that's almost completely reversed, with nearly the whole payment going to principal. Over the full 30 years, total interest paid comes to a little over $231,000 — more than the original loan amount, which is typical for a long-term loan at this kind of rate.
How extra payments change the schedule
An extra amount paid every month goes straight toward the principal, on top of the standard payment. Because next month's interest is calculated on a smaller balance, this has a compounding effect: paying slightly more each month both shortens the loan and reduces the total interest by more than the extra amount alone, especially if it starts early in the loan when the balance (and so the interest) is at its highest.
Which loans this works for
The same amortization math applies to any fixed-rate loan that pays down in equal installments, so this one calculator covers a mortgage or home loan, a car or auto loan, a personal loan, a business loan, and most fixed-rate home equity loans, among others. If you're financing a purchase with a down payment, enter the amount you're actually borrowing (the price minus your down payment) as the loan amount, since that's the balance interest is charged on.
Reading your schedule
- Payment # and date — which payment this is and roughly when it's due, based on your first payment date.
- Payment — the full amount due that month, including any extra payment you added.
- Principal and interest — how that payment splits between paying down the loan and the cost of borrowing.
- Balance — what's left to pay after that payment, which reaches zero on the final row.
Frequently asked questions
What is an amortization schedule?
It's a table showing every payment on a loan, broken down into how much goes to interest and how much goes to principal, along with the remaining balance after each one.
Why does more of my payment go to interest at the start?
Interest is calculated on the current balance, which is largest at the beginning of the loan. As the balance falls, the interest portion of each payment falls with it, and the principal portion grows, even though the total payment stays the same.
Can I download the amortization schedule?
Yes. Use "Download schedule (.csv)" to save the full table as a CSV file that opens directly in Excel, Google Sheets, or similar software, or "Print / save as PDF" to print it or save a PDF copy through your browser's print dialog.
How do extra payments affect an amortization schedule?
Each extra payment reduces the balance immediately, which reduces the interest charged the following month. Over the life of the loan, this adds up to paying it off sooner and paying meaningfully less interest overall, shown in the "pays off earlier" note above the schedule once you add an extra payment.
Does this work for 0% interest loans?
Yes. Enter 0 as the interest rate, and the calculator simply divides the loan evenly across the number of payments, with no interest shown on any row.
Is this the same as my bank's amortization schedule?
It uses the same standard formula banks use for fixed-rate loans, so the numbers should be very close. Small differences can come from rounding conventions, fees added on top of interest, or a different first payment date than your actual loan.
Is my loan information sent anywhere?
No. The schedule is generated entirely in your browser. Nothing you enter is uploaded or stored anywhere.
Does this handle biweekly payments?
Not as a separate payment frequency, but you can approximate the effect: paying biweekly instead of monthly works out to roughly one extra monthly payment a year. As a rough equivalent, try adding about one-twelfth of your monthly payment into "extra payment per month" and compare the result to the standard schedule.
Does this support balloon payments or interest-only periods?
No, this calculator shows a standard, fully-amortizing schedule, where every payment is the same amount and the loan reaches zero at the end of the term. A balloon loan has smaller payments followed by one large final payment, and an interest-only period defers principal payments for a set time; this tool doesn't model either, but you can still use it to see what a comparable fully-amortizing loan would look like for comparison.
Can I use this for an adjustable-rate mortgage (ARM)?
You can use it one rate period at a time. Calculate the schedule for the fixed-rate period, then when the rate is due to adjust, run it again with the new rate and the remaining balance and term, since this tool assumes one constant rate for the whole schedule it generates.
Can I open the schedule in Excel or Google Sheets?
Yes. "Download schedule (.csv)" saves a CSV file with every payment, which opens directly in Excel, Google Sheets, or any spreadsheet program.
Does this support multiple currencies?
Yes, the currency selector covers several common currencies; the schedule itself is currency-neutral, so pick whichever matches your loan.