If the principal and interest are equal, the amount of loan principal and interest repaid each month is the same (that is, the total amount of monthly repayment is the same, in which the interest decreases month by month and the principal increases month by month).

Monthly repayment amount = loan principal × (monthly interest rate× (1+monthly interest rate) repayment months) /(( 1+ monthly interest rate) repayment months-1)

In the case of average capital: repay the same amount of principal every month. With the reduction of the remaining principal, the monthly interest also decreases, so the monthly repayment amount also decreases accordingly.

Monthly repayment amount = loan principal/repayment months+(principal-accumulated amount of repaid principal) × monthly interest rate.

I. Loan interest

General compound interest is calculated on a monthly basis. Compound interest means that after the end of each interest period, the remaining interest should be added to the principal to calculate the interest of the next period. In this way, in each interest-bearing period, the interest of the previous interest-bearing period will become the principal of interest-bearing, that is, interest will accrue at interest, which is also commonly known as "rolling interest".

There are two ways to repay by installments, one is equal principal and interest, and the other is average capital. Due to the different repayment methods, the monthly loan interest is also different. However, no matter what kind of loan method, there is a unified calculation standard for bank loan interest.

Second, the loan interest calculation formula

Daily interest rate (0/000)= annual interest rate (%)÷360 = monthly interest rate (‰)÷30.

Monthly interest rate (‰) = annual interest rate (%)÷ 12

Current month loan interest = remaining principal of last month * monthly loan interest rate;

Principal paid in the current month = repayment amount in the current month-loan interest in the current month;

Remaining principal of last month = total loan-accumulated principal repayment;

So, how to calculate the loan interest? Below we can according to a practical example to illustrate:

If borrower A borrows RMB 6,543,800+from XX Bank, the loan period is 3 years, and the latest loan interest rate of 2065.438+03 is implemented, and the monthly loan interest rate is 0. 5 125% (at present, the annual interest rate of three-year loans is 6. 15%)。

First month loan interest = 100000*0. 5 125%=5 12。 5;

Principal paid in the first month = repayment amount in the first month (depending on repayment method) -52 1. 5;

Residual principal in the first month = 100000- (repayment amount in the first month -52 1. 5);

Second month loan interest ={ 100000- (first month repayment amount -52 1. 5)}*0。 5 125%