Calculation Of ESI - Variable Salary

Hello,
I am not sure of how to calculate ESI. I am aware that employee pays 1.75% and employer pays 4.75% but on what? I have the following break up in my salary - Basic, HRA, Medical Allowance, Conveyance Allowance, Ad-hoc Allowance, Special Allowance. I had the following questions
1) On what all of the above is ESI calculated?
2) What is the range of salary on which ESI is calculated? Till 15000 Per month?
3) There is another part of the salary that is variable salary (performance based). Should ESI calculation include that too?
Thanks in advance for helping me out.

Hello,
Let me tell me for your information that ESI is always calculated on gross salary. Whatever is your basic or cash in hand or CTC. it is always calculated on gross. And 15000/- should be the limit in terms of gross salary.
Regards

Hi,
1. ESIC is deducted from employees who are having gross salary less the 15000/-
2. All breakup mention by you will come under Gross Salary
3. Employee contribution is 1.75% of gross salary & Employer contribution is 4.75% of gross salary
4. All the fix parts of salary will be considered as gross salary and ESIC will be deducted; even the incentives if they are fixed incentives per month.
5. Any incentive or allowance which variable in nature and varies from month to month won’t be consider in Gross Salary.