Every evaporative cooler gets a score from 0 to 100% built from five factors, which maps onto the 5-point rating shown on the site (a 0% score would be 1.5 stars; a perfect score, 5). Each factor is scored against fixed reference points, not against the other products in the list, so adding a new model never moves another model’s rating. Coolers are grouped by airflow, under 2,000 CFM and 2,000 CFM and up, and airflow and tank size have their own scale for each group.
| Factor | Measures | Weight |
|---|---|---|
| Value | price per 1,000 CFM of airflow | 30% |
| Airflow | maximum airflow, CFM | 25% |
| Tank | water tank, gallons | 10% |
| Features | rigid cooling pads, oscillation, remote, hose hookup | 15% |
| Warranty | warranty length | 20% |
Where the numbers come from
Airflow, tank size, pad type and warranty come from the maker’s product page, spec sheet or manual, or the maker’s own copy on its Amazon listing. Coolers that give only a fan speed and no airflow aren’t ranked. Prices are checked at Amazon and the maker’s own store, and the lowest is used.
The factors
Value is the current price divided by the maximum airflow in thousands of CFM, on a log scale, so going from $200 to $100 counts as much as going from $100 to $50. $1,000 per 1,000 CFM scores zero and $60 full marks.
Airflow is the maker’s maximum airflow: under 2,000 CFM, 300 CFM scores zero and 1,800 CFM full marks; for 2,000 CFM and up, 2,500 CFM scores zero and 7,000 CFM full marks.
Tank is the water tank in gallons, which sets how long it runs between refills: under 2,000 CFM, 2 gal scores zero and 10 gal full marks; for 2,000 CFM and up, 8 gal scores zero and 30 gal full marks.
Features counts four things: rigid cellulose or honeycomb pads (which cool more and last longer than thin fiber pads), oscillating louvers, a remote, and a garden hose hookup so it never runs dry. Each is a quarter of the factor.
Warranty is the length of the warranty: 1 year scores zero and 3 years full marks.
What isn’t scored
The cooling area the maker claims, pad thickness, fan speeds, power draw and weight are listed but not scored. Cooling area claims rest on assumptions that differ from maker to maker; airflow is compared instead.
Missing data
If a figure isn’t published, that factor gets the neutral middle score (50) and the product page marks it as estimated.
Ties and discontinued models
Products are ranked by score within each group. Discontinued models stay listed but rank below every current model and can be hidden with the “Hide discontinued” filter.