Assuming the principal is 100 yuan and the monthly interest rate is 1%, the calculation method is as follows:100 *1%/30 * 30 =1yuan.
For example:
1. For example, if the monthly interest rate is 1%, the monthly loan or deposit is 1 00 yuan; Then the interest for next month 1 day is 65438+ one year 12 months' total interest in 0 yuan, which is 12 yuan. If it is less than one month, the interest for the remaining days will be calculated according to the current interest listed by the bank on that day. This is a simple and interesting algorithm;
2. The calculation of compound interest is more complicated. You need to use the accumulated interest and principal after each month as the principal of next month to calculate the interest of next month. Or take 100 yuan as an example to calculate compound interest. The interest in the first month is 1 yuan, the principal and interest are1kloc-0/yuan, and the interest in the second month is 1.0 1. And so on to get the compound interest and principal amount of the corresponding month.
The monthly interest rate is the monthly interest. The monthly interest rate is expressed as several thousandths of the principal. One thousandth is dividend, that is, 1% is 1.
Extended data
1. When calculating interest, the days of deposit should be counted as the beginning rather than the end, that is, from the date of deposit to the day before withdrawal;
2. No matter leap year, average year or month size, the whole year is 360 days, and every month is 30 days;
3. Calculated by year, month and day, the maturity date of various time deposits shall be subject to year, month and day. That is, from the date of deposit to the same day of the following year is a pair of years, and the date of deposit to the same day of next month is a pair of months;
4. Maturity date of time deposit. For example, if the legal holiday office is closed, you can withdraw money one day in advance, and the interest will be calculated according to the maturity. The procedure is the same as that of early withdrawal.
The calculation formula of interest: principal × annual interest rate (percentage) × deposit period.
If the interest tax is X( 1-5%)
Total principal and interest = principal+interest
The calculation formula of accrued interest is: accrued interest = principal × interest rate × time.
Accrued interest shall be accurate to two decimal places, and the number of interest-bearing days shall be calculated according to the actual holding days.
PS: The deposit term should correspond to the interest rate, not necessarily the annual interest rate, but also the daily interest rate and the monthly interest rate.
Refer to Baidu Encyclopedia-interest calculation formula