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Amortization Calculator

Build a loan amortization schedule with the monthly payment, total interest, and payoff date — and see how optional extra payments shorten the term and cut total interest.

$
years
months
%
$
$
$

Monthly Payment

$1,687.71

Total of Payments
$303,788.46
Total Interest
$103,788.46
Payoff Date
January 1, 2040
Interest Saved (from extra payments)
$0.00
Months Saved
0

Principal vs interest

Principal 66%, Interest 34%
  • Principal66%
  • Interest34%

Amortization schedule

PeriodInterestPrincipalBalance
Year 1$11,769.23$8,483.33$191,516.67
Year 2$11,246.00$9,006.57$182,510.10
Year 3$10,690.49$9,562.07$172,948.02
Year 4$10,100.72$10,151.84$162,796.18
Year 5$9,474.58$10,777.98$152,018.20
Year 6$8,809.82$11,442.75$140,575.45
Year 7$8,104.05$12,148.51$128,426.94
Year 8$7,354.76$12,897.80$115,529.13
Year 9$6,559.25$13,693.31$101,835.82
Year 10$5,714.68$14,537.89$87,297.94
Year 11$4,818.01$15,434.55$71,863.38
Year 12$3,866.04$16,386.52$55,476.86
Year 13$2,855.36$17,397.21$38,079.66
Year 14$1,782.34$18,470.23$19,609.43
Year 15$643.13$19,609.43$0.00
Monthly Payment$1,687.71View results

See exactly how a fixed-rate loan is paid off. Enter the loan amount, term, and rate to get the monthly payment, total interest, payoff date, and a full schedule that splits every payment into principal and interest. Add optional extra payments to see how much faster — and cheaper — the loan clears.

Formula

Each fixed monthly payment covers that month's interest first; the rest reduces the balance, so the interest portion shrinks every month. For a principal P, monthly rate r (annual rate ÷ 12), and n months:

Monthly payment = P × r / (1 − (1 + r)^−n)

Each month:  interest = balance × r
             principal = payment − interest  (+ any extra payment)
             balance   = balance − principal
Extra payments go entirely to principal, erasing all the future interest that principal would have cost — which is why paying a little extra early saves so much.

How a payment splits over time

StageInterest portionPrincipal portion
First paymentLargestSmallest
MidwayRoughly evenRoughly even
Final paymentSmallestLargest

Examples

$200,000 · 15 years · 6%

A $200,000 loan at 6% over 15 years has a monthly payment of $1,687.71. Over 180 payments you repay $303,788.46, of which $103,788.46 is interest.

Same loan + $200 extra per month

Adding $200 to every payment clears the same loan in about 152 months instead of 180 — roughly 28 months early — and cuts total interest by about $18,230.

Frequently asked questions

What is an amortization schedule?
It is a table listing every payment on a loan, splitting each one into the interest portion and the principal portion and showing the remaining balance afterward. Early payments are mostly interest; later payments are mostly principal, because interest is charged on a shrinking balance.
How is the monthly payment calculated?
With the standard amortization formula. For a principal P, a monthly rate r (the annual rate divided by 12), and n monthly payments, the payment is P × r ÷ (1 − (1 + r)^−n). That fixed amount covers each month's interest first, and the rest reduces the balance.
How do extra payments help?
Every extra dollar goes straight to principal, so it removes all the future interest that dollar would have accrued. Even a small extra monthly amount can shave years off the term and save thousands in interest. This calculator shows the new payoff date, the interest saved, and the months saved.
Why is so much of my early payment interest?
Because interest is charged on the outstanding balance, which is largest at the start. As the balance falls, the interest portion of each fixed payment shrinks and the principal portion grows, so the loan pays down faster and faster toward the end.
Does amortization work for all loans?
Amortization schedules apply to fixed-rate installment loans — mortgages, auto loans, personal and student loans. They don't model adjustable-rate loans, variable-rate loans, or revolving credit such as credit cards, whose rates or balances change over time.

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