Air purifiers, scored on five axes

Buy it if

• An open-plan living space rather than a bedroom-sized box
• You want one control and no app
• The washable fabric sleeve catching pet hair appeals to you

Skip it if

• You want a display showing particulate readings
• Carbon filtration for cooking smells is a priority

Buy it if

• Cooking smells and smoke, where the carbon stage earns its place
• You want replacement filters from more than one supplier
• Auto mode that responds to actual air quality

Skip it if

• You want the ionizer permanently gone rather than switched off each time
• A visible control panel light in a dark bedroom bothers you

Buy it if

• A room large enough that smaller units cycle constantly
• You want a particulate number rather than a coloured light
• Dual-sided intake suits where the unit has to sit

Skip it if

• Proprietary filters that cost real money every six months
• Floor space is tight — the footprint is substantial

Buy it if

• A bedroom or a nursery where night-time noise decides everything
• You want scheduling and a sleep mode from an app
• Cheap replacement filters matter over years of ownership

Skip it if

• A large or open-plan room — this will run flat out and lose
• You expect the plastics to survive being knocked around

Buy it if

• Allergy season in a large room, where throughput beats finesse
• You want mechanical controls that cannot lose firmware
• Filters stocked in every hardware store

Skip it if

• The unit will be anywhere near where someone sleeps
• You want auto mode driven by a sensor