Little Home Appliance

9 Air Purifiers for Rooms 700+ sq ft, Ranked by Running Cost

Room air cleaners whose ENERGY STAR room size rating is 700+ sq ft, sold in the US. Ranked cheapest to run first, estimated at 18.31¢/kWh (July 2026).

← All room sizes

9 ENERGY STAR certified models, from about $43 to $90 a year to run at the US average electricity rate. CADR (PM2.5) is shown for reference — a higher number clears smoke and fine particles faster, independent of running cost. See how we calculate running costs.

Top 5 cheapest to run

#1Most Efficient

Blueair 4312111000

705 sq ft · 235 kWh/yr

Est. $43/year to run

#2Most Efficient

Coway Airmega ProX;Airmega ProX(W);Airmega ProX(*);AP-3522F_US;AP-3522F_WT;AP-3522F_*

894 sq ft · 335 kWh/yr

Est. $61/year to run

#3Most Efficient

Coway Airmega ProX;AP-3522F_US;Airmega ProX(W);Airmega ProX(*);AP-3522F_WT;AP-3522F_*

894 sq ft · 335 kWh/yr

Est. $61/year to run

#4Most Efficient

Coway Airmega ProX

894 sq ft · 335 kWh/yr

Est. $61/year to run

#5

CUCKOO CAC-AH2810FNW

705 sq ft · 388 kWh/yr

Est. $71/year to run

All 9 models

Rank Brand Model Room size CADR (PM2.5) Energy use Est. cost/year
1 Blueair Most Efficient 4312111000 705 sq ft 444 235 kWh/yr $43
2 Coway Most Efficient Airmega ProX;Airmega ProX(W);Airmega ProX(*);AP-3522F_US;AP-3522F_WT;AP-3522F_* 894 sq ft 581 335 kWh/yr $61
3 Coway Most Efficient Airmega ProX;AP-3522F_US;Airmega ProX(W);Airmega ProX(*);AP-3522F_WT;AP-3522F_* 894 sq ft 581 335 kWh/yr $61
4 Coway Most Efficient Airmega ProX 894 sq ft 581 335 kWh/yr $61
5 CUCKOO CAC-AH2810FNW 705 sq ft 461 388 kWh/yr $71
6 CUCKOO CAC-F3010FW 856 sq ft 543 406 kWh/yr $74
7 Soleusair GA1-W 811 sq ft 529 463 kWh/yr $85
8 Winix Tower XQ 715 sq ft 471 486 kWh/yr $89
9 Fellowes Aeramax SV 803 sq ft 514 490 kWh/yr $90

Estimated running cost = annual kWh × 18.31¢/kWh (July 2026 US average). Your own rate may be higher or lower — check your bill. ENERGY STAR figures are lab-test results; real-world use varies. This list includes discontinued and not-yet-sold certified models, and some brands are white-label relabels of the same unit.