Honeywell HPA125B Air Purifier: CADR, Noise, Coverage & Specs
Last verified: Aug 23, 2026
Aug 2026
Quick verdict
The Honeywell HPA125B is best suited to medium rooms where high airflow and quiet minimum operation are priorities. Its 250 CFM smoke CADR supports about 388 sq ft at approximately 4.8 air changes per hour. Buyers should separately evaluate filter cost and maximum-speed noise before deciding.
Best for
- Living rooms and medium bedrooms
- Low-noise minimum settings
Consider alternatives if
- You need a verified maximum-speed noise figure
- Filter replacement interval or cost is a deciding factor
Verified strengths
- 250 CFM smoke CADR (~388 sq ft at ~4.8 ACH)
- 21 dB published minimum noise
- HEPA filtration (as published)
Verified limitations or missing information
- Maximum-speed noise is not in our sources
- Filter replacement interval is not verified
Honeywell HPA125B overview
The Honeywell HPA125B is a medium-room air purifier with a smoke CADR of 250 CFM. Based on our CADR-based room-size method, it is suitable for approximately 388 sq ft. It includes HEPA filtration and 21 dB minimum noise.
- Smoke CADR
- 250 CFM
- Recommended room size
- 388 sq ft
- Claimed coverage
- 530 sq ft
- Minimum noise
- 21 dB
- Filter type
- HEPA
- Weight
- 2.1 lb
- Last verified
- Aug 23, 2026
Honeywell HPA125B CADR and room size
Recommended room size is about 388 sq ft (CADR × 1.55). That is approximately 4.8 air changes per hour in a room with an eight-foot ceiling. The manufacturer figure of 530 sq ft corresponds to about 3.5 air changes per hour at the same ceiling height and is shown separately. Our recommended room size uses approximately 4.8 air changes per hour with an eight-foot ceiling. Manufacturer coverage figures may use a lower air-change rate and are shown separately.
Validated coverage from documentation is 530 sq ft.
Honeywell HPA125B noise level
Published minimum noise is 21 dB.
Maximum-speed noise is not in our sources.
Honeywell HPA125B filtration
Published filter type: HEPA.
Filter replacement interval is not verified in our sources.
Honeywell HPA125B smart features
Captures 99.97% of allergens, 3-in-1 filtration, AQSense Auto Mode, AHAM certified
Honeywell HPA125B specifications
- CADR (smoke)
- 250 CFM
- Recommended room size
- 388 sq ft
- Validated coverage
- 530 sq ft
- Manufacturer claimed coverage
- 530 sq ft
- Minimum noise
- 21 dB
- Filter type
- HEPA
- Weight
- 2.1 lb
About Honeywell air purifiers
Honeywell models in this catalog are compared by CADR, recommended room size, noise, and filter type.
Honeywell HPA125B comparisons
Compared with the Honeywell HPA300, the Honeywell HPA125B has 17% lower CADR.
What is the CADR of the Honeywell HPA125B?
Smoke CADR is 250 CFM.
What room size is the Honeywell HPA125B suitable for?
About 388 sq ft at approximately 4.8 air changes per hour with an eight-foot ceiling.
How loud is the Honeywell HPA125B?
Minimum reported noise: 21 dB.
Does the Honeywell HPA125B have Wi-Fi?
No published Wi-Fi or app control in our sources.
What filter does the Honeywell HPA125B use?
HEPA.
Methodology
Specifications are compiled from manufacturer documentation, product listings and other cited sources.
How we calculate recommended room size.
Sources
All air purifiers · Honeywell air purifiers · Best air purifiers for allergies · Methodology