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Loans

Amortization Calculator

Calculate a fixed monthly loan payment and see how each payment is split between principal and interest over the life of the loan.

Your loan

Enter the amount you borrow, the APR, and how long you have to repay it.

The amount you borrow.

The loan’s annual percentage rate.

Loan term unit

How long you have to repay the loan, in years or months.

Private by design

Your loan amount, APR, and term stay in your browser and are not sent to Calcora.

How this calculator works

  1. Enter your loan

    Add the amount you borrow, the APR, and the term in years or months.

  2. The monthly payment is set

    The calculator finds the fixed monthly payment that repays the loan, with interest, over exactly the number of payments in your term.

  3. Each payment covers interest first

    Every month, interest is charged on the remaining balance at the APR divided by 12. The rest of the payment reduces the principal.

  4. The last payment clears the balance

    Payments are rounded to the cent, so the final payment can differ slightly to bring the balance to exactly $0.

Amortization explained

What is an amortization schedule?

A table of every payment on a loan. For each one, it shows how much goes to interest, how much repays the amount borrowed, and what you still owe afterward.

Principal and interest

Principal is the amount you borrowed. Interest is what the lender charges for it, a percentage of the principal you still owe each month.

Why the interest portion shrinks

The payment stays the same, but each one lowers the balance. A lower balance creates less interest the next month, so a little more of every payment goes to principal.

Example amortization calculation

A $300,000 loan at 6.5% APR over 30 years, calculated the same way as the calculator above.

The monthly payment

Payment equals P times r, divided by 1 minus 1 plus r to the power of negative n.

P, the amount borrowed
$300,000.00
r, the monthly rate
6.5% ÷ 12
n, the number of payments
360
Monthly payment, rounded to the cent
$1,896.20

The first payment

Interest
$300,000.00 × 6.5% ÷ 12 = $1,625.00
Principal repaid
$1,896.20 − $1,625.00 = $271.20
Balance after payment 1
$299,728.80

Over 30 years, the 360 payments add up to $682,636.71: $300,000.00 of principal and $382,636.71 of interest. Principal becomes the larger part of the payment with payment 233, in year 20.

Assumptions

  • This is a general fixed-rate loan calculator, not a mortgage calculator. Property taxes, homeowners insurance, PMI, HOA dues, closing costs, and other fees are not included.
  • The APR you enter is used as the loan's interest rate and stays the same for the whole term. If your loan's APR includes fees, entering the interest rate instead gives a closer match to your lender's payment.
  • Interest is charged monthly at the APR divided by 12, on the balance at the start of each month.
  • One payment is made at the end of each month, starting next month, with no extra or missed payments.
  • The scheduled payment is rounded to the nearest cent, so the final payment can differ slightly to bring the balance to exactly $0.
  • Lenders may round or calculate interest differently, so their figures can differ slightly. Results are estimates for education, not financial advice.

How Calcora calculates

  • Every calculator explains the formula behind its result in plain language.
  • Calculators are designed to run in your browser, so your inputs are not sent to Calcora.
  • Results help you understand your options. They are not financial advice.
Read the methodology

Frequently asked questions

What is amortization?
Amortization is repaying a loan with equal payments over a set term. Each payment covers that month's interest and repays part of the principal, so the balance reaches $0 with the last payment.
How is the monthly payment calculated?
The calculator uses the standard fixed-rate formula, payment = P × r ÷ (1 − (1 + r)^−n), where P is the amount borrowed, r is the APR divided by 12, and n is the number of monthly payments. The result is rounded to the nearest cent. At 0% APR, the payment is the amount borrowed divided by the number of payments.
Why does more of my payment go to interest at the beginning?
Interest is charged on what you still owe, and at the start you owe the most. As each payment lowers the balance, the interest shrinks and more of the same payment goes to principal. The chart and schedule show exactly when principal becomes the larger part.
Why can the final payment be slightly different?
The exact payment usually has fractions of a cent, so it is rounded to the nearest cent. Over many payments, those fractions add up, and the final payment absorbs the difference so the balance ends at exactly $0. The longer the loan, the larger the difference can be: a few dollars on a typical 30-year loan, and sometimes more on longer terms.
Does this calculator include taxes, insurance, or fees?
No. It shows the loan's principal and interest only. A mortgage payment often also includes property taxes, homeowners insurance, and mortgage insurance, which are not part of this calculation.
Does Calcora store my loan information?
No. The calculation runs in your browser. Your loan amount, APR, and term are not sent to Calcora or saved, and they are cleared when you leave or reload the page.

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