What is an amortization schedule?

A month-by-month table showing how each payment splits between interest and principal, and what balance remains after it.

Why does so much early payment go to interest?

Interest is charged on the outstanding balance, which is largest at the start. As the balance falls the interest portion shrinks and more of each identical payment attacks the principal.

How do extra payments help?

Anything paid above the scheduled amount comes straight off the principal, which lowers every future interest charge and shortens the loan — often by years.

Amortization Calculator

Build a month-by-month amortization schedule showing principal, interest and balance.

Result

Monthly payment: $377.42
Total interest: $2,645.48
Total of payments: $22,645.48

Export:

Principal$20,000.0088.3%
Total interest$2,645.4811.7%

Loan balance over time

Yearly amortization schedule

Year	Principal paid	Interest paid	Ending balance
1	$3,611.11	$917.99	$16,388.89
2	$3,795.86	$733.24	$12,593.04
3	$3,990.06	$539.04	$8,602.98
4	$4,194.20	$334.90	$4,408.78
5	$4,408.78	$120.31	$0.00

Amortization schedule

Month	Payment	Principal	Interest	Balance
1	$377.42	$294.09	$83.33	$19,705.91
2	$377.42	$295.32	$82.11	$19,410.59
3	$377.42	$296.55	$80.88	$19,114.04
4	$377.42	$297.78	$79.64	$18,816.26
5	$377.42	$299.02	$78.40	$18,517.24
6	$377.42	$300.27	$77.16	$18,216.97
7	$377.42	$301.52	$75.90	$17,915.45
8	$377.42	$302.78	$74.65	$17,612.67
9	$377.42	$304.04	$73.39	$17,308.63
10	$377.42	$305.31	$72.12	$17,003.33
11	$377.42	$306.58	$70.85	$16,696.75
12	$377.42	$307.85	$69.57	$16,388.89
13	$377.42	$309.14	$68.29	$16,079.76
14	$377.42	$310.43	$67.00	$15,769.33
15	$377.42	$311.72	$65.71	$15,457.61
16	$377.42	$313.02	$64.41	$15,144.59
17	$377.42	$314.32	$63.10	$14,830.27
18	$377.42	$315.63	$61.79	$14,514.64
19	$377.42	$316.95	$60.48	$14,197.69
20	$377.42	$318.27	$59.16	$13,879.43
21	$377.42	$319.59	$57.83	$13,559.83
22	$377.42	$320.93	$56.50	$13,238.91
23	$377.42	$322.26	$55.16	$12,916.64
24	$377.42	$323.61	$53.82	$12,593.04
25	$377.42	$324.95	$52.47	$12,268.09
26	$377.42	$326.31	$51.12	$11,941.78
27	$377.42	$327.67	$49.76	$11,614.11
28	$377.42	$329.03	$48.39	$11,285.08
29	$377.42	$330.40	$47.02	$10,954.67
30	$377.42	$331.78	$45.64	$10,622.89
31	$377.42	$333.16	$44.26	$10,289.73
32	$377.42	$334.55	$42.87	$9,955.18
33	$377.42	$335.94	$41.48	$9,619.24
34	$377.42	$337.34	$40.08	$9,281.89
35	$377.42	$338.75	$38.67	$8,943.14
36	$377.42	$340.16	$37.26	$8,602.98
37	$377.42	$341.58	$35.85	$8,261.40
38	$377.42	$343.00	$34.42	$7,918.40
39	$377.42	$344.43	$32.99	$7,573.97
40	$377.42	$345.87	$31.56	$7,228.10
41	$377.42	$347.31	$30.12	$6,880.79
42	$377.42	$348.75	$28.67	$6,532.04
43	$377.42	$350.21	$27.22	$6,181.83
44	$377.42	$351.67	$25.76	$5,830.16
45	$377.42	$353.13	$24.29	$5,477.03
46	$377.42	$354.60	$22.82	$5,122.43
47	$377.42	$356.08	$21.34	$4,766.35
48	$377.42	$357.56	$19.86	$4,408.78
49	$377.42	$359.05	$18.37	$4,049.73
50	$377.42	$360.55	$16.87	$3,689.18
51	$377.42	$362.05	$15.37	$3,327.12
52	$377.42	$363.56	$13.86	$2,963.56
53	$377.42	$365.08	$12.35	$2,598.48
54	$377.42	$366.60	$10.83	$2,231.89
55	$377.42	$368.13	$9.30	$1,863.76
56	$377.42	$369.66	$7.77	$1,494.10
57	$377.42	$371.20	$6.23	$1,122.90
58	$377.42	$372.75	$4.68	$750.16
59	$377.42	$374.30	$3.13	$375.86
60	$377.42	$375.86	$1.57	$0.00

What an amortization schedule shows

Amortization is the bookkeeping behind a fixed-payment loan. The payment stays constant, but the schedule reveals how each one is carved into an interest piece and a principal piece. The interest piece equals the current balance times the monthly rate, and everything left over reduces the balance.

Watching the schedule month by month makes the mechanics obvious: the interest column starts high and falls steadily, the principal column starts low and rises, and the balance column glides toward zero by the final row.

Reading the table and charts

Each row of the schedule is one payment. The principal and interest columns always add up to the payment (give or take a rounding cent on the last row, which is trued up to clear the balance exactly).

The donut chart sums those columns over the whole loan so you can see total principal against total interest at a glance. The balance line plots the ending balance at each year end, giving a clean picture of how quickly the debt disappears.

Putting the schedule to work

An amortization schedule is more than a curiosity — it is a planning tool.

Spot how little principal early payments retire, which explains slow payoff at the start.
Estimate the payoff balance for any month if you plan to sell or refinance.
Model extra payments by imagining the balance dropping faster than the table shows.
Compare two rates or terms by reading off total interest from each schedule.

Formula

payment = P·r / (1 − (1+r)⁻ⁿ); each month: interest = balance·r; principalPaid = payment − interest

Frequently asked questions

What is an amortization schedule?: A month-by-month table showing how each payment splits between interest and principal, and what balance remains after it.
Why does so much early payment go to interest?: Interest is charged on the outstanding balance, which is largest at the start. As the balance falls the interest portion shrinks and more of each identical payment attacks the principal.
How do extra payments help?: Anything paid above the scheduled amount comes straight off the principal, which lowers every future interest charge and shortens the loan — often by years.