A portable air purifier is small in size and generally sits on a table or in the corner of a room. These are energy-efficient options to provide air purification where you need it most, such as in an area with a high amount of cooking or pets. These are cost-effective and can be carried from one room to the next, taking it where you need it the most. These are a great option for smaller homes or homeowners concerned with efficiency.
Whole home air purifiers offer a built-in air purification solution. These are either filter-based purifiers that work at the intake point of your HVAC system, or they are duct-based purifiers installed directly in the air duct path of your duct system. Because they only work when your HVAC system is running, your system must be running all the time, making them highly inefficient for home if you do not use your system constantly. If your home is large and you regularly have your ducts cleaned, this may be a better option for you.