Blueair Blue Pure 511 Air Purifier review
A small bedroom or home office on the tightest budget
By Tom Calder · Updated 24 July 2026 · Price checked against our tracker
The cheapest purifier on this list at £99, and its 38 m² coverage suits a single small-to-medium room rather than anything bigger. Blueair replaced the older 411/411+ with this 511 model in the UK, so treat it as the current comparable rather than a downgrade.
Confirmed consistently at £99 across three UK retailers as of Jul 2026.
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- Lowest price on this list at £99
- HEPASilent filter combines particle and carbon filtration in one stage
- Compact enough for a small bedroom or office
- Smallest stated room coverage on this list at 38 m², so it won't suit an open-plan space
- Blueair's own noise figures aren't fully consistent across their own materials, so treat the dB rating as approximate
- CADR is a converted figure rather than a figure Blueair publishes directly in m³/h
Key specs
| Room size | 38 m² |
| CADR | ~208 m³/h (converted from cfm, not Blueair-published) |
| Filter | HEPASilent combination particle and activated carbon filter |
| Noise (min) | 21 dB |
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