Loan/Installment Calc Free online general loan & installment calculator. Supports equal principal & interest and interest-only repayment modes. Calculate monthly payments, total interest, and the true annual rate (IRR) to understand the real cost of your loan.

Comparison of Two Repayment Methods：

• Equal Principal and Interest： This is the most common repayment method. Its main feature is a **fixed monthly payment**, making it easy to remember and plan for financially. In the early stages of repayment, interest makes up a higher portion of the monthly payment, while the principal is lower. Over time, the interest portion gradually decreases, and the principal portion increases. The total interest paid is typically higher than with the equal principal method.
• Interest-Only (Balloon)： During the entire loan period, you only repay interest each month. In the final period, you repay all the principal plus that period's interest. Common in some credit and business loans.

True Annual Rate (IRR) 是什么？

IRR (Internal Rate of Return) is the international standard for measuring the true cost of a loan. It accounts for all fees (interest, service fees, etc.) and converts them into an equivalent annualized rate. Compared to the nominal rate, the IRR better reflects the actual cost of your loan.