Deposit interest = principal * deposit term * deposit interest rate.

If the interest rate of 1 0,000 yuan fixed-term three-month deposit is 1. 1%, then deposit interest = principal * maturity * deposit interest rate = 1 0,000 * 3/12 *1%.

Note that the listed interest rates of banks are all annualized interest rates, not the deposit interest rate of three months 1. 1%. The specific monthly interest rate should be converted from the annual interest rate to the monthly interest rate. For example, three months is the result of 3/ 12, because there are 12 months in a year. Similarly, the bank's current interest rate is an annualized interest rate of one year (calculated by 360 days), and it is impossible to get a deposit interest rate of 0.35% (four major banks) every day.

If the deposit interest rate of 1 1,000 yuan is 2.75%, then the total deposit interest = principal * maturity * deposit interest rate = 1 1,000 * 32.75% = 825 yuan.

Note that annual conversion is not required, because it is annualized interest rate.

Loan interest:

There are two types of loan interest. One is consumer credit loans such as credit cards, which exist in the form of charging fees. The specific interest rate should be calculated by the internal rate of return formula or by the RATA function in excel. The annualized interest rate of general consumer credit loans hovers between 15%- 18%, and the specific interest can be calculated through the specific interest rate, which is not discussed here.

The other is mortgage and other loans. Mortgage can be divided into two repayment methods. But either way, the interest returned every month is: monthly interest = residual principal * mortgage interest rate/12.

Monthly repayment average capital = principal+interest = loan principal/repayment months+(repaid principal) * loan interest rate/12, as shown in the above figure.

Equal principal and interest for monthly repayment = principal+interest = monthly repayment principal+(repaid principal) * loan interest rate/12, as shown in the above figure.

Note: No matter the average capital or the equal principal and interest, the repayment principal and interest and the monthly repayment amount will change with the change of the benchmark interest rate of the central bank's five-year loan, so the result calculated without mortgage calculator is not a fixed figure. The mortgage calculator only calculates the current loan interest rate, which will be adjusted with the adjustment of the benchmark interest rate of the central bank.