Is social security purchased based on how much the labor contract pays?

Salary does not include social security. China's relevant laws, social security belongs to the employer mandatory payment, the employer for the workers to buy social security costs should not be included in the wages of workers, that is, the total wage does not include social security costs. Legal basis: Article 3 of the Provisions on the Composition of the Total Wage Bill: The total wage bill refers to the total amount of labor remuneration paid directly to all employees of each unit within a certain period of time. The calculation of total wages shall be based on all labor remuneration paid directly to the employees. Article 4 The total amount of wages consists of the following six components: (1) hourly wages; (2) piecework wages; (3) bonuses; (4) allowances and subsidies; (5) overtime and overtime wages; (6) wages paid under special circumstances.