Understanding CTC vs. Salary
Everybody is confusing the salary with CTC. CTC is the quantum only known to the management and is not directly related to the employees. It is used to determine the labor cost, and the HR/Personnel department informs the management about the total amount incurred for each employee.
This total amount includes the salary in total (bifurcated into basic, transport allowance, HRA, allowances, etc. - to be determined separately by consulting the employee during the interview or as per company rules), plus the employer's share of PF, ESI, LWF, and bonus. Gratuity is considered in the CTC only after an employee completes five years of service.
Therefore, the salary to be paid for 23 days in your specified case would be calculated as follows: 13,000 divided by 30 and multiplied by 23.