The calculation of the Provident Fund (PF) contribution is based on the 'PF wages' of an employee. As per the Employees' Provident Fund and Miscellaneous Provisions Act, 1952, the PF wages is capped at ₹15,000 per month. This means that the employer's contribution is calculated as 12% of ₹15,000 (i.e., ₹1,800) irrespective of the actual salary of the employee.
However, if the employee wishes to contribute more than the mandatory contribution, they can do so voluntarily. This is known as Voluntary Provident Fund (VPF). The VPF can be up to 100% of the employee's basic salary and dearness allowance. But remember, the employer is not obligated to match the additional contribution made by the employee under VPF.
In your case, if the employee's salary is ₹1 lakh and you want to calculate the PF, you can consider ₹15,000 as the PF wages for the employer's contribution. If the employee wants to contribute more, they can do so under VPF.
Please refer to the official EPF India website
https://www.epfindia.gov.in for more detailed information.