Loan Interest Calculator

How to use the loan interest calculator

1. Enter amount, rate, and term — type the amount you're borrowing, the annual interest rate (%), and the loan term (months or years).
2. Choose a repayment method — pick equal payments, equal principal, or interest-only.
3. Calculate — your monthly payment, total interest, total repayment, and a period-by-period repayment schedule are shown.

Equal Payments (Amortizing)

Your monthly payment (principal + interest) stays the same for the entire loan term. Early on, more of each payment goes toward interest and less toward principal; over time the principal share grows. Because the payment is fixed, it's easier to plan your budget.

Equal Principal

The principal portion of each payment stays the same, while the interest is calculated on the remaining balance — so your payment shrinks over time. Payments start higher, but total interest is the lowest of the three methods.

Interest-Only (Bullet)

You pay only interest each month during the loan term, then repay the entire principal in one lump sum at maturity. Monthly payments are the lowest, but total interest is the highest of the three methods.

Which repayment method should I choose?

If your goal is to reduce total interest, equal principal is the better choice; if you want to manage a consistent monthly amount, equal payments is better. Interest-only has the lowest monthly burden but the highest total interest, so it's mainly chosen for short-term funds or when you plan to repay before maturity.

How is the annual interest rate applied?

The annual rate is divided by 12 to get a monthly rate, which is applied to the remaining principal each month. As the principal decreases, the interest decreases too. This calculator uses loan-repayment logic (interest on the outstanding balance), not deposit-style compound interest.