Calculator · free · runs in your browser
Loan Amortization Calculator
Enter the amount, rate and term of a loan to see the monthly payment, total interest and the full payment schedule. Lending to a friend or family member? Attach the schedule to apromissory note in one click.
Equal monthly payments (fixed-rate, fully amortizing). Nothing you type leaves your browser.
Monthly payment
- Total interest
- Total paid
- Last payment
| # | Date | Payment | Interest | Principal | Balance |
|---|
Fill in the amount and term to see the schedule (rate and date are optional — 0% and today are used if blank).
How to read the schedule
- Interest is what the month cost: the remaining balance × the monthly rate (annual rate ÷ 12).
- Principal is the part of the payment that actually reduces the debt. It grows every month as the interest part shrinks.
- Balance is what is still owed after that payment. Paying it off early means paying this figure, not the sum of the remaining payments.
Need to push a due date back on an existing loan? The loan extension agreement can attach a fresh schedule for the remaining balance.
Frequently asked questions
How is the monthly payment calculated?
The calculator uses the standard fixed-payment (annuity) formula: the annual rate is divided by 12 to get a monthly rate, and the payment is set so that the loan is fully repaid after the chosen number of months. Each payment first covers the interest accrued on the remaining balance that month; the rest reduces the principal. A 0% loan simply splits the amount equally.
Why does the interest portion shrink over time?
Interest is charged on what is still owed. Early on the balance is high, so most of the payment goes to interest; as the balance falls, more of each identical payment goes to principal. That is why paying extra early in a loan saves the most interest.
What does the schedule show?
One row per payment: the date, the payment amount, how much of it is interest, how much reduces the principal, and the balance left afterwards. The final payment is adjusted by a few cents so the balance ends at exactly zero.
Can I attach this schedule to a promissory note?
Yes. Our free promissory note generator has an “Add amortization schedule” option that builds the same table from the note’s own amount, rate and dates and appends it as “Schedule A” to the PDF and Word download. The loan extension agreement offers the same for the remaining balance.
Does the schedule replace the repayment terms in the loan document?
No. The schedule illustrates the arithmetic; the written terms of the note (amount, rate, dates, what counts as late) are what the parties actually agree to. If they differ, the document controls, so make sure both match before signing.
Is there a legal limit on the interest rate?
Many states cap the interest that can be charged on private loans (often called usury limits), and the rules vary by state, loan size and lender type. This calculator does the math for any rate you enter; it does not check whether that rate is allowed where you are. Check your state’s rules or ask a professional for larger loans.
General information and arithmetic, not legal or financial advice. Interest-rate limits and lending rules vary by state; check them before relying on a rate.