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Amortization Calculator

Loan amortization

Every payment split into interest and principal, with the contractual schedule and the extra-payment schedule side by side.

Loan
The quoted nominal annual rate, divided by twelve for each monthly payment — the lending convention. That is not the same as an effective annual rate.
For terms that are not a whole number of years.
First payment date
This is the date of the first payment, not the origination date.
Later payments keep this day, clamped to the length of each month.
Extra principal (optional)
Paid alongside every scheduled payment.
Which payment of each year carries the annual amount.
Scheduled monthly payment
$2,155.01

Principal and interest only, for 360 scheduled payments. Adding extra principal does not change this amount — it shortens the loan instead.

Total interest$425,80454.9% of everything you pay
Total principal$350,000
Total of payments$775,804
Number of payments360Ending December 1, 2055
Extra principalNone enteredAdd extra principal to see the interest and time it saves
Where your money goes over the full term
  • Principal: $350,000 (45.1%)
  • Interest: $425,804 (54.9%)
Contractual schedule against the extra-payment schedule
MetricStandard planWith extra paymentsDifference
Monthly required payment$2,155.01$2,155.01
Payoff dateDecember 1, 2055December 1, 2055
Number of payments360360
Total interest$425,804$425,804
Total paid$775,804$775,804
Extra principal paid$0$0

No extra principal is entered, so both columns describe the same loan.

Scroll the table sideways on a narrow screen to see every column.

What different amounts of extra principal would do to this loan
StrategyExtra cash a yearPayoffSooner byTotal interestInterest saved
No extra payments$0December 1, 20550 months$425,804$0
+100 a month$1,200July 1, 20523 years 5 months$367,231$58,573
+200 a month$2,400November 1, 20496 years 1 month$324,334$101,470
+500 a month$6,000August 1, 204411 years 4 months$242,996$182,807

Preset strategies computed from the loan above. They are arithmetic, not a recommendation about what to do with spare cash.

Scroll the table sideways on a narrow screen to see every column.

Schedule detail
Amortization by year
YearStarting balanceScheduled paymentsExtra paymentsPrincipal repaidInterest paidEnding balance
1$350,000$25,860$0$4,101$21,759$345,899
2$345,899$25,860$0$4,365$21,495$341,534
3$341,534$25,860$0$4,646$21,214$336,888
4$336,888$25,860$0$4,945$20,915$331,943
5$331,943$25,860$0$5,263$20,597$326,680
6$326,680$25,860$0$5,601$20,259$321,079
7$321,079$25,860$0$5,962$19,899$315,118
8$315,118$25,860$0$6,345$19,515$308,773
9$308,773$25,860$0$6,753$19,107$302,019
10$302,019$25,860$0$7,187$18,673$294,832
11$294,832$25,860$0$7,650$18,210$287,182
12$287,182$25,860$0$8,142$17,718$279,040
13$279,040$25,860$0$8,666$17,195$270,375
14$270,375$25,860$0$9,223$16,637$261,152
15$261,152$25,860$0$9,816$16,044$251,336
16$251,336$25,860$0$10,448$15,413$240,888
17$240,888$25,860$0$11,120$14,741$229,769
18$229,769$25,860$0$11,835$14,025$217,934
19$217,934$25,860$0$12,596$13,264$205,338
20$205,338$25,860$0$13,406$12,454$191,932
21$191,932$25,860$0$14,269$11,592$177,663
22$177,663$25,860$0$15,186$10,674$162,477
23$162,477$25,860$0$16,163$9,697$146,314
24$146,314$25,860$0$17,203$8,657$129,111
25$129,111$25,860$0$18,309$7,551$110,802
26$110,802$25,860$0$19,487$6,373$91,315
27$91,315$25,860$0$20,740$5,120$70,574
28$70,574$25,860$0$22,074$3,786$48,500
29$48,500$25,860$0$23,494$2,366$25,006
30$25,006$25,860$0$25,006$855$0

Yearly rows are aggregates of the monthly schedule, which is the calculation itself.

Scroll the table sideways on a narrow screen to see every column.