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Fan and Frost

Cooling matched to the room

The right cooling for one hot room

Trusted because we show our math, not because we say so. We have not tested a single one of these products — what we do instead is compile the published specifications, compute the running cost at a cited electricity rate, and print every formula so you can check it.

Late afternoon sun through a bedroom window with the curtain drawn back
Units we claim to have tested
0
Sponsored placements
0
Free products accepted
0
Products with sourced specs
145

Everyone in this category says they tested twenty units. We have not tested any, and we say so. What we have instead is every published specification traced to the page it came from, the ENERGY STAR certified datasets, and arithmetic you can reproduce with a calculator — the method is published in full.

The picks

What we’d buy, by category

The top pick from each of our 80 ranked lists. Prices are live from Amazon where we hold them and read “check price” where we do not — verified October 19, 2026.

Lowest published draw

Air King 9723

Air King 9723 20" Commercial Grade Box Fan

Air King · 9723

65 W on low for 1,463 CFM — 22.5 CFM per watt, the only box fan efficiency figure that can be calculated from published numbers rather than guessed.

$46.25 · View on Amazon

$58.00 · 20% off · price as of October 19, 2026

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Most air on a desk

Air King 9106 (sold at retail as 3151G)

Air King 9106 16" Commercial Grade Oscillating Table Fan

Air King · 9106 (sold at retail as 3151G)

1,710 CFM on 77 W with oscillation — the only desk-sized fan with a published airflow table, and it is four to nine times what a typical desk fan moves.

$89.65 · View on Amazon

Price as of October 19, 2026

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Best drum fan

Air King 9230

Air King 9230 30" Industrial Grade Pivoting Drum Fan

Air King · 9230

7,400 CFM on 255 W, at 29.0 CFM per watt. More air than any portable fan we can source specs for, and the best efficiency on the site outside ceiling fans.

$319.99 · View on Amazon

$433.99 · 26% off · price as of October 19, 2026

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Best humidity-sensing fan

Delta SIG80-110MH

Delta BreezSignature SIG80-110MH Ventilation Fan

Delta · SIG80-110MH

110 / 60 / 30 CFM, 0.1 sones and 15.3 CFM per watt on a 6-inch duct, with humidity and motion sensing. Certified identically to the non-sensing version of the same fan.

$212.00 · View on Amazon

Price as of October 19, 2026

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Best for drying laundry

Midea MDUDMB-50AEN8-BB0F

Midea Dehumidifier, 50 pints/day

Midea · MDUDMB-50AEN8-BB0F

49.67 pints a day, about 23.5 liters, at IEF 2.08 L/kWh. The only household-name brand above the certified efficiency ceiling, and the cheapest per liter on this page.

$241.59 · View on Amazon

$258.11 · 6% off · price as of October 19, 2026

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Best hygrometer

AcuRite 01080M

AcuRite 01080M Pro Accuracy Temperature and Humidity Gauge

AcuRite · 01080M

±2% RH from 10 to 90%, ±0.5 F, a manual calibration option and 24-hour plus all-time high/low records. The only pick that is both cheap and candid about where its accuracy applies.

$21.99 · View on Amazon

Price as of October 19, 2026

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Start from the room, or the product

Six sections

People arrive at this either knowing they want a tower fan, or knowing only that their bedroom is 84°F. Both routes end at the same hardware; the second usually has a better answer.

A tower fan running beside an open window in a lived-in bedroom in late afternoon light

58 pages

Fans

Tower, box, pedestal, window, desk and circulator fans, sorted by what each actually does to a room.

Start here →
A basement utility room with exposed brickwork and laundry appliances

29 pages

Dehumidifiers

Portable and whole-home dehumidifiers ranked on certified IEF and annual kWh, with sizing and the noise figure nobody publishes.

Start here →

Why this site is different

We do the arithmetic in public

Running cost, computed and cited

Every cost on this site is (watts ÷ 1000) × hours × rate, at 18.34¢/kWh from the EIA, with the formula printed next to the answer. A 19 W fan is 84¢ a month of nights; a 1,300 W portable AC is $57.

Sized from the official table

Not “20 BTU per square foot” but the ENERGY STAR table, with all four of its adjustments — including the +4,000 BTU for a kitchen that almost every calculator omits, and which moves most open-plan rooms a whole capacity band.

A skip pick on every list

All 214 of our ranked lists name a product we recommend against, and why. A list where everything is great is a list nobody should believe — and the skip is usually a popular product bought for the wrong room.

The one table most people need

What size air conditioner your room needs

Measure length by width in feet and read across. Then +10% if the room is very sunny, −10% if heavily shaded, +600 BTU per person beyond two, and +4,000 BTU in a kitchen.

ENERGY STAR room air conditioner sizing table
Room area (sq ft)Capacity needed (BTU/h)
100 up to 1505,000
150 up to 2506,000
250 up to 3007,000
300 up to 3508,000
350 up to 4009,000
400 up to 45010,000
450 up to 55012,000
550 up to 70014,000

Source: ENERGY STAR, Room Air Conditioners. ENERGY STAR notes the capacities “are calculated based on an 8-foot ceiling.” The full chart, with the adjustments.

The full walkthrough, with four rooms worked start to finish →

Read these first

The four pages that carry the argument

How this is funded

Amazon commissions, and nothing else

When you buy through a link here, Amazon pays us a percentage at no cost to you. There are no sponsored posts, no paid placements and no free products — and commission does not affect a ranking. Our picks skew toward correctly-sized, efficient units, which are frequently the cheaper option and therefore pay us less. On the window AC page we recommend a 6,000 BTU unit costing $55 a year to run and explicitly tell you not to buy the 24,000 BTU unit that would earn us several times as much.

Full disclosure · Editorial policy · How we pick