The tool
What CADR does this room actually need?
Clean air delivery rate is the only number on an air-cleaner box that is comparable between brands. EPA publishes a minimum for each room size, this tool reads that table and nothing else.
What CADR does this room actually need?
Reads the EPA table, and nothing else. No interpolation, ever.
Want the whole table at once instead of one room at a time?
Compare the six published rowsHow the tool answers, and how it refuses
Exact row
A room that lands on a published row gets that row's minimum, verbatim, with the source shown.
Between rows
The tool rounds up to the larger published row and says so, CADR is a minimum, never a target to interpolate towards.
Beyond the table
Past 600 sq ft there is no stated minimum. The tool gives the largest published figure as a floor and refuses to extrapolate.
The two refusals, in full
No CADR for gases, odours or VOCs
CADR is defined for particles, smoke, dust and pollen. There is no published CADR for gases, odours or VOCs, so no minimum exists for your room size. An air cleaner advertised as removing odours or VOCs is not making a claim you can compare between brands the way you can compare a particle CADR.
No MERV-by-room-size table
MERV rates a furnace or HVAC filter by how well it captures particles, not by the size of room it can serve. EPA publishes no MERV-by-room-area table, so there is no figure to give you here. What EPA does say is that filters rated MERV 13 and above must demonstrate at least 50% removal efficiency for the smallest particles tested.
The table the tool reads
| Room area (sq ft) | Minimum CADR (cfm) |
|---|---|
| 100 | 65 |
| 200 | 130 |
| 300 | 195 |
| 400 | 260 |
| 500 | 325 |
| 600 | 390 |
Source: U.S. Environmental Protection Agency, Guide to Air Cleaners in the Home (2nd edition) (retrieved 2026-08-30). The published figures assume an 8-foot ceiling, if yours is higher, EPA advises choosing a higher CADR than the table shows.