Coway Airmega 450S: CADR, room size and running cost
Smoke CADR 443 cfm · Room size 687 sq ft (ENERGY STAR) · 399 kWh/yr ≈ $73.06/yr electricity (estimate)
Certified specs
| Smoke CADR | 443 cfm |
|---|---|
| Dust CADR | 454 cfm |
| Pollen CADR | 450 cfm |
| PM2.5 CADR | 449 cfm |
| ENERGY STAR effective room size | 687 sq ft (1.55 × smoke CADR, per 10 CFR 429.68) |
| Annual energy use | 399 kWh/yr |
| Integrated energy factor | 6.6 cfm/W |
| Smoke CADR per watt | 6.55 cfm/W |
| Ozone emissions (reported) | 0 ppb |
| Technology | Fan and Filter |
| Filter types listed | HEPA-Type |
| Automatic mode | Air Quality Sensor |
| Connected (app/Wi-Fi) | Yes (Wi-Fi) |
| ENERGY STAR Most Efficient | No |
| Markets | United States, Canada |
| Date certified | 2025-01-02 |
| ENERGY STAR partner | Coway Co., Ltd. |
| Source | ENERGY STAR record 4005914 (also listed as record(s) 4005916, 4005915) · Product Finder page |
How many air changes per hour would it give?
Estimate: air changes per hour (ACH) = smoke CADR × 60 ÷ room volume, at the top fan speed used for the CADR test. Real-world ACH is usually lower (lower fan speeds, furniture, filter loading).
| Room | ACH, 8 ft ceiling | ACH, 9 ft ceiling | AHAM sizing |
|---|---|---|---|
| 100 sq ft | 33.2 | 29.5 | Meets AHAM 2/3 rule |
| 150 sq ft | 22.1 | 19.7 | Meets AHAM 2/3 rule |
| 200 sq ft | 16.6 | 14.8 | Meets AHAM 2/3 rule |
| 300 sq ft | 11.1 | 9.8 | Meets AHAM 2/3 rule |
| 400 sq ft | 8.3 | 7.4 | Meets AHAM 2/3 rule |
| 500 sq ft | 6.6 | 5.9 | Meets AHAM 2/3 rule |
| 700 sq ft | 4.7 | 4.2 | Below AHAM 2/3 rule |
AHAM's 2/3 rule: choose a smoke CADR of at least 2/3 of the room's area (8 ft ceiling). By that rule this model suits rooms up to about 664 sq ft.
Estimated yearly electricity cost
| Where | Residential rate | Per year | Per month |
|---|---|---|---|
| Louisiana | 12.72¢ | $50.75 | $4.23 |
| U.S. average | 18.31¢ | $73.06 | $6.09 |
| California | 33.61¢ | $134.10 | $11.18 |
| Hawaii | 48.00¢ | $191.52 | $15.96 |
Estimate = 399 kWh/yr × rate. Rates: EIA Table 5.6.A, July 2026 (preliminary). Filter replacement cost is not included (data gap: not in ENERGY STAR data). Use your own rate and hours.
On battery during an outage (estimate): 399 kWh ÷ 5,840 active hours ≈ 68 W average, which runs slightly high because the annual figure includes standby. A 1,024 Wh portable power station at an assumed 85% inverter efficiency would run it about 13 h. Top fan speed can draw more. Try other stations in the runtime calculator on our power station site.
Similar CADR from other brands
| Model | Smoke CADR (cfm) | ENERGY STAR room size (sq ft) | Energy use (kWh/yr) | Est. electricity/yr* |
|---|---|---|---|---|
| Blueair 4312111000 | 455 | 705 | 235 | $43.03 |
| Blueair 3613111100 | 443 | 687 | 259 | $47.42 |
| Blueair 6712211000 | 393 | 609 | 336 | $61.52 |
| Levoit LAP-C601S-WUS | 391 | 606 | 387 | $70.86 |
| Cuckoo CAC-AH2810FNW | 455 | 705 | 388 | $71.04 |
| Levoit LAP-C601S-WUSR | 394 | 611 | 389 | $71.23 |
| Winix Tower XQ | 461 | 715 | 486 | $88.99 |
*Estimate: ENERGY STAR annual kWh × U.S. average residential rate 18.31¢/kWh (EIA, July 2026 (preliminary)). ENERGY STAR's annual figure assumes 16 hours/day of operation under the DOE test procedure.
Compare this model side by side with any other · All Coway models
See Coway air purifiers on the manufacturer's site (plain link, not an affiliate link)
We have not tested this product. Figures are as listed in ENERGY STAR data retrieved 2026-10-17.