Finding out the effectiveness of your filter is easy. Just find out the MERV Rating. MERV stands for Minimum Efficiency Reporting Value. This was developed by the American Society of Heating, Refrigeration and Air Conditioner Engineers - ASHRAE. The values on the MERV rating vary from 1 to 16. The higher the MERV value, the better the efficiency of the filter in catching airborne particles. Also, it considers the air flow through your HVAC. A dirty or restrictive filter may cause low airflow and result in HVAC system malfunction.
The following table will give you more clarity on the MERV Rating: