Loan Calculator

Monthly payment, total interest and amortization schedule

How each repayment method works

Amortizing loan (equal monthly payments)

Most mortgages and car loans work this way. You pay the same amount every month: P × r × (1+r)ⁿ ÷ ((1+r)ⁿ − 1), where P is the loan amount, r is the monthly rate (annual rate ÷ 12) and n is the number of months. Early payments are mostly interest; later payments are mostly principal.

Equal principal

The principal is split evenly across the term and interest is charged on the remaining balance. The first payment is the largest and each one after is smaller. Total interest is lower than an amortizing loan.

Interest-only (balloon)

You pay interest only and repay the full principal at maturity. Total interest equals loan amount × annual rate × years.

Example: 300,000 at 6.5% for 30 years

Frequently asked questions

Which repayment method costs less in total?

Equal principal repayment has the lowest total interest because the balance falls faster. Its first payments are higher, though. A standard amortizing loan keeps every payment the same, which is easier to budget.

What is an interest-only (balloon) loan?

You pay only interest each month and repay the whole principal at the end of the term. Monthly payments are the lowest, but total interest is the highest of the three methods.

Why is my lender’s figure slightly different?

This calculator charges interest monthly as balance × annual rate ÷ 12 and rounds to the cent. Lenders may use daily interest, fees, taxes, insurance (such as PMI or escrow), grace periods or extra payments, so their numbers can differ.

Does it work with any currency?

Yes. Enter amounts in whatever currency you use. Results are shown as plain numbers with two decimal places.

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