PureAirIndex · Room sizing
Air purifier room size calculator
How much clean-air delivery does your room need? These results use smoke CADR, not a box’s maximum coverage claim.
Your room
eACH = equivalent air changes per hour from filtration. The default 4.8 is a sizing comparison, not a medical recommendation. Enter the full connected floor area for an open-plan space.
Required smoke CADR
300 ft² × 8 ft × 4.8 ÷ 60
117 of 247 snapshot records meet the unrounded requirement.
The displayed target rounds up to a whole cfm. Matching uses the exact calculated value. Certified CADR may not be available at the quieter speed you intend to use.
Read the room-coverage studyMatching ENERGY STAR records
Lowest sufficient smoke CADR first. Not a quality, price or noise ranking.
Captured 2026-10-20 (UTC) · 117 matching records · Smoke CADR in cfm
| Model / ENERGY STAR ID | Smoke CADR | Reported area | Area at your eACH / height |
|---|---|---|---|
| Atmosphere BLUE 316500K* 316500K* · ID 4587207 | 192 | 298 ft² | 300 ft² |
| WOOZOO APF-25 APF-25 · ID 4515595 | 197 | 305 ft² | 307 ft² |
| Clorox TYPE AP30 11010 · ID 4439466 | 206 | 319 ft² | 321 ft² |
| Midea KJ350G-S1 KJ350G-S1 · ID 4439559 | 208 | 322 ft² | 325 ft² |
| TaoTronics TT-AP003 TT-AP003 · ID 4439560 | 208 | 322 ft² | 325 ft² |
| LAGO LAPKJ350GS1BLK LAPKJ350GS1BLK · ID 4439561 | 208 | 322 ft² | 325 ft² |
| PURE CODE APU-S1WUS APU-S1WUS · ID 4439562 | 208 | 322 ft² | 325 ft² |
| Midea 793K19A 793K19A · ID 4439563 | 208 | 322 ft² | 325 ft² |
| Govee H7122 H7122 · ID 4528766 | 210 | 326 ft² | 328 ft² |
| GoveeLife H7122 H7122 · ID 4576981 | 210 | 326 ft² | 328 ft² |
| Clorox Type AP39 11091 · ID 4005673 | 213 | 330 ft² | 332 ft² |
| Sharp KJ400G-L1A-SH Lite KJ400G-L1A-SH Lite · ID 4695474 | 214 | 332 ft² | 334 ft² |
What the result does—and does not—mean
Smoke CADR measures clean-air delivery for test particles. It does not establish removal of gases or odors, noise, filter lifespan, or health outcomes. These model matches assume the listed certification output and do not model placement, mixing, doors, or ongoing pollution sources.
Reported room area is preserved from ENERGY STAR; the last column is our separate calculation at your selected settings. They can differ because their rating assumptions and rounding differ. See the methodology and downloadable source data.