What is the calculation formula of social security contribution base?

Legal analysis: Generally speaking, my salary income in the last year is the payment base. Social insurance shall be paid with reference to the local average wage, with 60% of the average wage as the guaranteed payment base and 300% of the average wage as the capped payment base. Generally, my salary income in the previous year is the base of payment. (1) If the wage income of employees is higher than 300% of the local average wage of employees in the previous year, 300% of the local average wage of employees in the previous year will be used as the payment base. (two) if the wage income of employees is lower than 60% of the local average wage of employees in the previous year, 60% of the local average wage of employees in the previous year shall be the payment base. (3) If the employee's salary is between 300% and 60%, it shall be declared according to the facts. When it is impossible to determine the wage income of employees, the payment base shall be determined according to the local average wage of employees in the previous year published by the local labor administrative department.

Legal basis: Article 60 of the Social Insurance Law of People's Republic of China (PRC) * * * The employer shall declare by itself and pay the social insurance premium in full and on time. Except for legal reasons such as force majeure, the payment shall not be postponed or reduced. The social insurance premiums that employees should pay shall be withheld and remitted by the employer, and the employer shall inform me of the details of paying social insurance premiums on a monthly basis. Individual industrial and commercial households without employees, part-time employees who have not participated in social insurance in the employing units and other flexible employees can pay social insurance premiums directly to the social insurance premium collection agencies.