As we head towards winters, the air quality of entire northern India, especially, is deteriorating. With metrics like PM2.5 and PM10 hitting levels as high as 600 and 999 respectively for outdoors, it goes without saying the air inside in a room will be far more polluted. There’s no denying that the current air quality is dangerous for health and getting an air purifier seems like the only choice to breathe slightly cleaner air. When it comes to buying an air purifier, the cost of filter replacement and the lifespan of the air filter should be considered. Also, it is important to check whether you can easily replace the filter or not. Here are X affordable air purifiers with easy filter replacement under Rs 20,000.