About this site
Quick answer
AirQualityCalc works out what a room actually needs before it recommends anything: 223 generated sizing pages, 5 calculators, and a catalog of 351 real product listings behind them.
Why this site exists
Air purifiers are sold on a number with a unit nobody explains. A box says it covers 1,500 square feet, and the figure is true at some air change rate the box does not print. The same machine in the same room is either adequate or hopeless depending on a number that was left out.
The arithmetic that fixes this takes one line, so every page here shows it. Floor area times ceiling height times the air changes you want, divided by sixty, gives the clean air delivery rate the room needs. Once you have that number, most of the marketing stops mattering.
What is different here
Three things. The calculators refuse: if no single machine can serve a room at the rate asked for, they say so and recommend two units rather than the largest thing on the page. The filter cost is treated as part of the price, because over five years the filters frequently cost more than the machine. And the site is plain about ozone, which is the one genuine safety question in this category.
How it pays for itself
Affiliate links, disclosed in the footer of every page and explained in full on the affiliate disclosure. The sizing arithmetic does not know what anything costs, and no commission changes what a room needs.