The Purifier Intelligence Database

Building this database surfaced something we did not set out to find. The gaps are not evenly distributed — they cluster precisely around the specifications that would let you predict what a purifier costs to own rather than what it costs to buy.

On the water side, water recovery, tank material, free service are published by fewer than half the models we track. Water recovery is the starkest: it determines how many litres go down your drain for every litre you drink, and it is almost never stated.

On the air side, the same pattern holds for hepa grade, noise (min). HEPA grade is the one worth dwelling on — most brands claim "HEPA" and never name the grade, and H11 and H14 are very different filters.

Specifications are transcribed from manufacturer literature and normalised by a parser rather than by hand, so that "20.5 - 51 dB", "Up to 55 dB" and "24 dB on sleep mode" become comparable fields instead of three incompatible strings. Where a brand publishes only one end of a range, we record only that end.

Derived fields are computed by stated formula: five-year cost is purchase price plus five years of running cost; CADR per ₹1,000 is clean air delivery divided by street price; clean air per watt is CADR divided by rated power. Each is labelled as derived wherever it appears.

Running-cost figures are our own estimates of consumables plus routine service, and are labelled as estimates in the table, in the exports and in the structured data. They are the only numbers here that are not either published by the brand or computed from published inputs.

When a figure cannot be read confidently from the source, the field stays empty. The parser is deliberately conservative — a marketing claim such as "2x the recovery of conventional RO" contains a number but no measurement, and is recorded as not published.

The database is published under a Creative Commons Attribution 4.0 licence. You may reuse it in articles, research, comparison tools or teaching material, commercially or otherwise, provided you credit BestPurifier and link to this page.

The link matters more than the credit. Every figure here carries a verification date, and a reader who can reach the source can see whether the number they are reading is still current. A citation without a link turns a dated figure into a permanent one.