The calculation methods of interest after the loan contract expires are product interest method and transaction interest method. Cumulative interest method accumulates the daily loan balance according to the actual number of days, and multiplies the accumulated amount by the daily interest rate to calculate interest; The interest calculation method calculates interest one by one according to the preset interest calculation formula.

Legal objectivity:

Provisions on Several Issues Concerning the Application of Laws in the Trial of Private Lending Cases Article 26 If the lender requests the borrower to pay interest at the interest rate agreed in the contract, the people's court shall support it, except that the interest rate agreed by both parties exceeds four times the market quotation of one-year loan at the time of the establishment of the contract. The "one-year loan market quotation" mentioned in the preceding paragraph refers to the one-year loan market quotation issued monthly by the National Interbank Funding Center authorized by the People's Bank of China from August 20th, 20th, 20th19th.