Air purifier room size: sq ft to m²
In one line: to convert, 1 m² ≈ 10.76 sq ft (÷10.76 to go from sq ft to m²). But a "covers X sq ft" claim is often optimistic — check the CADR and work out the real air changes for your room instead.
Quick conversions
| Square feet | ≈ Square metres | Room |
|---|---|---|
| 100 sq ft | 9.3 m² | Small bedroom / nursery |
| 160 sq ft | 15 m² | Bedroom / small office |
| 270 sq ft | 25 m² | Double bedroom / lounge |
| 430 sq ft | 40 m² | Large living room |
| 650 sq ft | 60 m² | Open-plan / kitchen-diner |
Formulas: m² = sq ft ÷ 10.76 · sq ft = m² × 10.76.
Why "coverage area" can mislead
Many "covers up to X sq ft" figures assume a low air-change rate (sometimes just 1–2 per hour) — enough to nudge the air, not to properly clean a room. A unit rated for a big area at 1 ACH may only manage 2–3 ACH in half that space. That's why comparing measured CADR — and dividing it by your room volume for the real ACH — is more reliable than trusting the coverage claim.
From area to the size you need
Once you've got your room in m², head to what size air purifier do I need for the CADR to aim for, then sanity-check running cost with the running-cost calculator.
Next step
See units listed with real CADR (not just coverage claims) at Best Air Purifier UK.
FAQ
How many sq ft is 30 m²? About 323 sq ft (30 × 10.76).
Should I trust the "covers X sq ft" number? Treat it as a rough ceiling. Compare CADR and target 4–6 air changes per hour for real cleaning.