Hi,
The normal practice is of calculating PF as 12% of basic. However, this is only the employers contribution. Another 12% is deducted as Employees contribution. So total is 24%.
As far as I know, there is no maximum limit . e.g. If an employee has Rs. 50000/ basic Salary p.m. then 12% comes to Rs. 6000. Hence the total amount deducted would be Rs. 12000/
Thanks and Regards,
Karan