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Amortization Calculator

Generate a complete amortization schedule and see how extra payments reduce your total interest.

Updated June 2026 · Editorial standards

Loan details

$
%
$
Monthly payment
$1,896
Total interest
$382,633
Total paid
$682,633

Over 30 years you'll pay $382,633 in interest — 128% of the loan principal.Try adding an extra monthly payment to see how much you could save.

Balance remaining over time

Principal vs interest — total cost

Amortization schedule

YearPrincipalInterestBalance
Year 1$3,353$19,401$296,647
Year 2$3,578$19,177$293,069
Year 3$3,817$18,937$289,252
Year 4$4,073$18,681$285,179
Year 5$4,346$18,409$280,833
Year 6$4,637$18,118$276,196
Year 7$4,947$17,807$271,249
Year 8$5,279$17,476$265,970
Year 9$5,632$17,122$260,338
Year 10$6,009$16,745$254,328
By the KalkWise Editorial Team Reviewed for accuracy Updated June 2026

What is the amortization calculator?

In short

An amortization schedule shows exactly how each loan payment is split between interest and principal. Early payments are mostly interest; over time the principal portion grows. The monthly payment formula is M = P × [r(1+r)ⁿ] / [(1+r)ⁿ − 1], where P is the loan amount, r is the monthly rate, and n is the number of payments.

This amortization calculator generates a full payment-by-payment schedule for any fixed-rate loan. You can see principal, interest, and remaining balance for every month — plus model the effect of extra payments on your payoff date and total interest.

How to use this calculator

  1. 1Enter the loan amount.
  2. 2Enter the annual interest rate.
  3. 3Choose the loan term in years.
  4. 4Optionally add an extra monthly payment to see how it speeds up payoff.
  5. 5Review the monthly payment, total interest, and full amortization schedule.

The formula

M=P·r·(1+r)n(1+r)n−1
The monthly payment (M) is derived from the loan amount, the monthly interest rate, and the total number of payments. Each payment first covers that month's interest; the remainder reduces the principal.
M
— Monthly payment
P
— Principal (loan amount)
r
— Monthly interest rate (annual rate ÷ 12)
n
— Total number of payments (months)

Worked example

The scenario

$300,000 loan at 6.5% for 30 years with an extra $200/month payment.

gives

The result

Base monthly payment: $1,896. With the extra $200 you pay off the loan 5 years 8 months early and save $67,400 in interest.

Common use cases

  • Understanding the true cost of a mortgage over its full term
  • Seeing how even small extra payments dramatically reduce interest
  • Comparing 15-year vs 30-year amortization side by side
  • Planning when your loan balance will drop below 80% (to remove PMI)

Limitations & assumptions

  • Assumes a fixed interest rate for the entire term — adjustable-rate loans will differ.
  • Does not include taxes, insurance, HOA fees, or PMI in the payment.
  • Rounding in monthly calculations may cause small discrepancies vs your lender's schedule.

Frequently asked questions

An amortization schedule is a complete table showing each scheduled payment over the life of a loan, broken down into the principal and interest portions, along with the remaining balance after each payment.

Disclaimer: KalkWise calculators are provided for general informational and educational purposes only and do not constitute financial, investment, tax, or legal advice. Results are estimates based on the figures you enter and the assumptions described above. Actual outcomes will vary. Consult a qualified professional before making financial decisions.