Usually when an employee resigns or retires the leaves will be calculated in the same manner as salaries. It depends on your company as to how many days per week do you work and the calculations thereof. If it is 5 day week like in many IT sector, the calculation for 25k salary [as example] will be 25000/20 x [the number of days worked in the month].
Encashment of leaves in some companies are done on the basic salary when the leaves [earned/privilege] are over and above 60[as per the Shops & Establishment Act] or as per the company policy.
An employee who is leaving the company has to be cleared of his earned leaves apart from the other benefits applicable.
Thanks and Regards
20th August 2018 From India, Hyderabad