Every car dryer gets a score from 0 to 100% built from six 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. Dryers are grouped by type (hose dryers, corded handhelds and cordless), and all three use the same scale, so a hose dryer and a cordless blower with the same score are rated the same.
| Factor | Measures | Weight |
|---|---|---|
| Motor power | rated input watts, or peak horsepower when no wattage is published | 25% |
| Air speed | published air speed | 15% |
| Airflow | published airflow volume in CFM | 15% |
| Value | price per kW of rated input power, or per peak HP when no wattage is published | 15% |
| Features | filtered air, heated air, speed control, reach and mobility | 20% |
| Warranty | warranty length | 10% |
Where the numbers come from
Power, air speed, airflow, features and warranty come from the maker’s spec sheet or product page, an authorized dealer’s copy of the maker’s spec table, or the maker’s own copy on a retail listing. Air speed and airflow are taken as the maker publishes them; none of these figures is an independent measurement. Where a maker’s own figures conflict (for example a title that gives one wattage and a bullet that gives another, or an air speed in feet per minute that doesn’t match the same page’s mph figure), the figure is left out rather than guessed. Prices are checked at Amazon and the maker’s own store, and the lowest price at a store the page links to is used.
The factors
Motor power is the rated input power in watts, on a log scale: 500 W scores zero and 2,400 W full marks. When a maker publishes peak horsepower but no wattage, the horsepower is scored instead on its own log scale, 0.5 HP scoring zero and 8 HP full marks, and marked estimated, since peak horsepower is a marketing figure rather than a rated input.
Air speed is the published air speed, converted to mph, on a log scale: 150 mph scores zero and 750 mph full marks. Makers quote it in feet per minute, mph or meters per second; the product page shows the figure as published.
Airflow is the published airflow volume in cubic feet per minute, on a log scale. For hose dryers and corded handhelds, 60 CFM scores zero and 400 CFM full marks. Cordless jet-fan blowers rate airflow at the fan, which gives much larger numbers than a hose dryer’s rating at the nozzle, so the two aren’t directly comparable; cordless blowers are scored on their own scale, 300 CFM scoring zero and 800 CFM full marks.
Value is the current price divided by the rated input power, in dollars per kW, on a log scale: $400 per kW scores zero and $75 per kW full marks. When only peak horsepower is published, value is the price per peak HP instead, $150 per HP scoring zero and $20 per HP full marks, marked estimated.
Features is 25% for filtered intake air, 25% for heated air, 20% for speed control (a variable dial or two or more settings), 15% for reach (a hose or cord of 20 ft or more, or no cord at all) and 15% for wheels, a wall mount or a remote.
Warranty is the maker’s warranty: none scores zero and 5 years full marks. A longer motor-only warranty is shown on the product page but not scored.
What isn’t scored
Weight, noise, current draw, number of motors, heat rise above ambient, battery voltage and capacity, runtime and release date are listed but not scored. Noise is published for too few models to compare.
Missing data
Motor power and airflow are the figures that most separate one dryer from another, so a dryer whose maker publishes neither wattage nor horsepower gets zero for motor power, and one with no published airflow gets zero for airflow. Both are marked estimated. Warranty works the same way: a maker that doesn’t publish one gets no warranty counted, so that factor scores zero and is marked estimated. Air speed and value get the neutral middle score (50) when they can’t be worked out, and the product page marks them as estimated. Features score neutral only when none of them is published; a feature the maker doesn’t mention otherwise counts as absent.
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.