What we score
- Clean-air speed (CADR). The biggest factor. Lab results beat maker figures.
- Filtration. A stated H13 or H14 grade, and real carbon for smoke.
- Running cost. Filters and power over three years.
- Perth fit. Smoke sensor, washable pre-filter, local filter supply and noise.
What the scores mean
| 4.5 to 5 | Buy it. Best in class for Perth homes. |
| 4.0 to 4.4 | Good in the right room, with a catch. |
| 3.5 to 3.9 | Works, but there's better value. |
| Under 3.5 | Hard to recommend at the price. |
Realistic room sizes
Box figures assume one air change an hour. We use three and a half to four, with a 2.4 m ceiling:
Room (m²) = CADR ÷ (2.4 × 3.5 to 4)
For the Levoit 400S, 340 ÷ 9.6 is 35 m² and 340 ÷ 8.4 is 40 m², so we list 35 to 40 m². Units without a CADR are estimated from lab results and marked “Not published”.
Prices
In AUD, as typically sold in Australia, checked on 7 October 2026 against Amazon Australia, the makers' Australian stores and major retailers. Prices change often, sometimes daily; the retailer's page always has the current price. Where Amazon Australia sells a unit itself or through the brand's Australian distributor, our buttons go there first.
Sources
- HouseFresh lab tests: Levoit 400S, Winix, Dyson, Levoit 600S, Levoit Vital 100S. BreatheSafeAir: Xiaomi Air Purifier 6.
- CHOICE testing of units sold in Australia (members only).
- Maker specs from Breville, Levoit, Winix, Coway, Philips, Dyson and Xiaomi.
- Air data from WA DWER stations via the World Air Quality Index project.
- Health research is listed on the smoke and indoor air guides.
Changelog
- 7 October 2026 (prices). All prices rechecked. Several changed a lot: the Breville fell to $448, the Levoit 400S rose to $399 and the Levoit 300S to $274 after the standard models sold out in Australia, and the Philips 2000i is $549. Ratings changed to match: Levoit 400S 4.5 to 4.2, Levoit 300S 4.0 to 3.5, Philips 2000i 4.2 to 3.8. The Breville is now our best overall pick and the Xiaomi Air Purifier 6 our best value. Buy buttons now go to Amazon Australia first where it sells the unit.
- 7 October 2026. Added four reviews: Levoit Core 600S, Levoit Vital 100S, Xiaomi Air Purifier 6 and Philips 600i. The Breville is no longer described as the fastest unit we rate; the lab-tested Core 600S now is. New page: best air purifiers for Perth homes. Wider page layout with a sidebar.
- 30 September 2026. Amazon buttons now go straight to each product on Amazon.com.au.
- 24 September 2026. Simpler design, shorter guides and photos. Added a live Swan River camera, a Perth air quality page with a five-day smoke forecast, a page for every review, best-for pages, three comparisons, six new guides, calculators on their own pages, calendar filter reminders, a printable smoke-day poster, a free website widget and an installable app. The live reading now skips stations whose data is delayed.
- 23 September 2026. Rebuilt as separate pages, with new health guides, calculators and a sortable table. Live readings now come from WA's DWER stations. Philips room size corrected to 40 to 45 m². Removed statistics we couldn't trace to a source.
- August 2026. Prices checked.