How is an amortization schedule calculated?

For each payment: interest = previous balance × rate per period; principal = payment − interest; new balance = previous balance − principal.

Why does most of my early payment go to interest?

Interest is charged on the outstanding balance, which is largest at the start of the loan.

Does an extra payment change the schedule?

Yes. An extra principal payment lowers the balance, so every later payment carries less interest and the loan ends sooner.

Can I print or copy the schedule?

Yes. The table is plain HTML, so you can select it and paste it into a spreadsheet or print the page.

Amortization Schedule Formula and Table

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Amortization Schedule Calculator

An amortization schedule lists every payment of a loan and splits it into interest and principal. Each period, interest is charged on the balance at the start of the period (balance × r). Whatever is left of the fixed payment after interest reduces the principal, and the new balance carries into the next period. After the last payment the balance is exactly zero.

Formula

Interest_k = B_k−1 × r Principal_k = P − Interest_k B_k = B_k−1 − Principal_k

Where

P: level payment = L × r ÷ [1 − (1 + r)⁻ⁿ]
B_k: balance after payment k (B₀ = loan amount L)
r: interest rate per period
n: number of payments

Calculator

Loan amount

Annual interest rate (%)

Loan term (years)

Payments per year

Result and step-by-step solution

Payment per period

483.32

60 payments, total interest 3,999.20.

Rate per period and number of payments
r = 6%12 = 0.005; n = 5 × 12 = 60
Discount term
(1 + r)⁻ⁿ = (1 + 0.005)⁻⁶⁰ = 0.7413722
Apply the payment formula
P = 25,000.00 × 0.0051 − 0.7413722 = 483.32
First payment
Interest = 25,000.00 × 0.005 = 125.00; principal = 483.32 − 125.00 = 358.32; balance = 24,641.68
Repeat for every payment
Each period the interest is charged on the lower balance, so more of the same payment goes to principal.

Yearly summary

Year	Paid	Interest	Principal	Balance
1	5,799.84	1,379.76	4,420.08	20,579.92
2	5,799.84	1,107.14	4,692.70	15,887.22
3	5,799.84	817.70	4,982.14	10,905.09
4	5,799.84	510.42	5,289.42	5,615.66
5	5,799.84	184.18	5,615.66	0.00

Full schedule

#	Payment	Interest	Principal	Balance
1	483.32	125.00	358.32	24,641.68
2	483.32	123.21	360.11	24,281.57
3	483.32	121.41	361.91	23,919.66
4	483.32	119.60	363.72	23,555.93
5	483.32	117.78	365.54	23,190.39
6	483.32	115.95	367.37	22,823.03
7	483.32	114.12	369.20	22,453.82
8	483.32	112.27	371.05	22,082.77
9	483.32	110.41	372.91	21,709.86
10	483.32	108.55	374.77	21,335.09
11	483.32	106.68	376.64	20,958.45
12	483.32	104.79	378.53	20,579.92
13	483.32	102.90	380.42	20,199.50
14	483.32	101.00	382.32	19,817.18
15	483.32	99.09	384.23	19,432.94
16	483.32	97.16	386.16	19,046.79
17	483.32	95.23	388.09	18,658.70
18	483.32	93.29	390.03	18,268.68
19	483.32	91.34	391.98	17,876.70
20	483.32	89.38	393.94	17,482.76
21	483.32	87.41	395.91	17,086.86
22	483.32	85.43	397.89	16,688.97
23	483.32	83.44	399.88	16,289.10
24	483.32	81.45	401.87	15,887.22
25	483.32	79.44	403.88	15,483.34
26	483.32	77.42	405.90	15,077.43
27	483.32	75.39	407.93	14,669.50
28	483.32	73.35	409.97	14,259.53
29	483.32	71.30	412.02	13,847.51
30	483.32	69.24	414.08	13,433.42
31	483.32	67.17	416.15	13,017.27
32	483.32	65.09	418.23	12,599.04
33	483.32	63.00	420.32	12,178.71
34	483.32	60.89	422.43	11,756.29
35	483.32	58.78	424.54	11,331.75
36	483.32	56.66	426.66	10,905.09
37	483.32	54.53	428.79	10,476.29
38	483.32	52.38	430.94	10,045.35
39	483.32	50.23	433.09	9,612.26
40	483.32	48.06	435.26	9,177.00
41	483.32	45.89	437.44	8,739.57
42	483.32	43.70	439.62	8,299.94
43	483.32	41.50	441.82	7,858.12
44	483.32	39.29	444.03	7,414.09
45	483.32	37.07	446.25	6,967.84
46	483.32	34.84	448.48	6,519.36
47	483.32	32.60	450.72	6,068.64
48	483.32	30.34	452.98	5,615.66
49	483.32	28.08	455.24	5,160.42
50	483.32	25.80	457.52	4,702.90
51	483.32	23.51	459.81	4,243.10
52	483.32	21.22	462.10	3,780.99
53	483.32	18.90	464.42	3,316.58
54	483.32	16.58	466.74	2,849.84
55	483.32	14.25	469.07	2,380.77
56	483.32	11.90	471.42	1,909.35
57	483.32	9.55	473.77	1,435.58
58	483.32	7.18	476.14	959.44
59	483.32	4.80	478.52	480.92
60	483.32	2.40	480.92	0.00

How to use the formula

The payment itself comes from the loan payment formula. The schedule then shows the pattern that surprises many borrowers: the payment never changes, but the interest part shrinks and the principal part grows every period, because interest is always charged on a smaller balance than the time before.

The default example is a 25,000 loan at 6% over 5 years with monthly payments of 483.32. In month one, 125.00 is interest and 358.32 principal; by the final month, interest is 2.40 and principal 480.92. Total interest over the loan is 3,999.20. For loans with more than one payment a year, a yearly summary appears above the full table. The figures match Excel’s IPMT and PPMT functions payment for payment.

Frequently asked questions

How is an amortization schedule calculated?: For each payment: interest = previous balance × rate per period; principal = payment − interest; new balance = previous balance − principal.
Why does most of my early payment go to interest?: Interest is charged on the outstanding balance, which is largest at the start of the loan.
Does an extra payment change the schedule?: Yes. An extra principal payment lowers the balance, so every later payment carries less interest and the loan ends sooner.
Can I print or copy the schedule?: Yes. The table is plain HTML, so you can select it and paste it into a spreadsheet or print the page.

Last reviewed: September 26, 2026. Calculations run in your browser and were checked against numpy-financial, SciPy and published spreadsheet examples.