Interest calculation formula: interest = principal × interest rate × deposit period.

1, if the interest period is a whole year (month), the interest formula is:

Interest = principal × year (month )× year (month) interest rate

2. If the interest-bearing period is a whole year (month) and days, the interest-bearing formula is:

Interest = principal × year (month )× year (month) interest rate principal × odd days × daily interest rate

Extended data:

The interest rate conversion formula for RMB business is (note: common for deposits and loans):

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

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

At the same time, banks can choose to convert all interest-bearing periods into actual days to calculate interest, that is, 365 days per year (366 days in leap years), and each month is the actual number of days in the Gregorian calendar of the current month. The interest-bearing formula is as follows:

Interest = principal × actual days × daily interest rate

The calculation formula is essentially the same, but because the interest rate conversion is only 360 days a year, the actual daily interest rate will be calculated on the basis of 365 days a year, and the result will be slightly biased. Which formula is used specifically, the central bank gives financial institutions the right to choose independently. Therefore, the parties and financial institutions can agree on this in the contract.