Loan Interest Calculator

Total interest cost of a loan and how it splits by year — compare simple vs amortizing interest.

Enter values

Result

Total interest (amortizing)

$10,870.20

Monthly payment: $1,268.13
Interest if charged as simple interest: $20,000.00; Flat-rate loans charge interest on the original amount — much more expensive.
Effective cost: 21.74%

Amortization schedule (yearly)

Period	Principal paid	Interest paid	Balance
Year 1	10,699.11	4,518.44	39,300.89
Year 2	11,819.45	3,398.1	27,481.44
Year 3	13,057.1	2,160.45	14,424.35
Year 4	14,424.35	793.2	0

Total interest cost of a loan and how it splits by year — compare simple vs amortizing interest.

Also known as: interest on loan, total loan interest, interest cost.

Enter loan amount, interest rate, term.
The result updates instantly as you type — press Calculate (or Enter) at any time.
Review the breakdown shown under the main result.
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Total interest = n × payment − P

Using the values pre-filled in the calculator above:

the calculator returns: