Every portable air conditioner 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. Units are grouped by how they take power (DC or battery, and 110 V AC) and ranked within each group.
| Factor | Measures | Weight |
|---|---|---|
| Value | price per 1,000 BTU of cooling | 30% |
| Efficiency | cooling BTU per watt drawn | 25% |
| Noise | rated sound level, usually in sleep mode | 15% |
| Weight | how much there is to carry | 10% |
| Warranty | warranty on the unit | 20% |
Where the numbers come from
Cooling and heating capacity, rated power, noise, weight and warranty come from the maker’s product page or spec sheet where one exists, and otherwise from the seller’s listing. Most budget units have only an Amazon listing, so their figures are the seller’s claims and no independent test backs them. Prices are checked at Amazon and the maker’s own store; the lowest price at a store the page links to is used.
The factors
Value is the current price divided by the rated cooling capacity, per 1,000 BTU, on a log scale: $300 per 1,000 BTU scores zero and $60 full marks.
Efficiency is the rated cooling capacity divided by the rated cooling power in watts, so higher means more cooling from the same battery: 7 BTU per watt scores zero and 11 full marks. EcoFlow’s published ratings are 9.3 BTU per watt for the Wave 2 and 8.8 for the Wave 3. Budget listings claim 10 to 13, with no test behind them, so a claim above 11 scores the same as 11. A unit whose maker publishes only an average or eco-mode draw, not a rated one, gets the neutral middle score and is marked estimated.
Noise is the lowest rated sound level, usually in sleep mode, in dB: 60 scores zero and 40 full marks. Makers measure at different distances, and a few claims (such as 30 dB for a compressor) are not credible, so the product page notes when a figure is the upper end of a quoted range.
Weight is the maker’s stated weight in pounds: 50 lb scores zero and 15 lb full marks. Amazon’s shipping weights are not used. A bundle that includes a battery is weighed with the battery.
Warranty is the warranty on the unit: 1 year scores zero and 2 years full marks. A maker that doesn’t publish one gets no warranty counted, so that factor scores zero and is marked estimated, which is true of most of the budget brands.
What isn’t scored
Heating capacity, app control, whether the price includes a battery and the 110 V versus DC input are listed but not scored. Heating has its own page.
Missing data
If a figure isn’t published, that factor gets the neutral middle score (50) and the product page marks it as estimated. The exception is warranty, described above.
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.