CADR to Room Size Converter
Enter your air purifier's CADR rating to find out exactly how many square feet it can effectively clean
Air Purifier Specifications
Coverage Area Results
Coverage by Air Quality Need:
Visual Room Size Comparison
Personalized Recommendations
Your Air Purifier Can Handle:
- ✓Bedroom: Up to 375 sq ft for allergy relief
- ✓Living Room: Up to 469 sq ft for daily use
- ✓Open Plan: Up to 938 sq ft for basic filtration
Room Size Guidelines:
Understanding Coverage Areas
Air purifier coverage depends on how many times per hour you want the air cleaned (ACH):
- 2 ACH:Minimum for general air quality (largest coverage)
- 4 ACH:Recommended for good air quality
- 5 ACH:Ideal for allergies and asthma
- 6 ACH:Hospital-grade for severe conditions
CADR Rating Guidelines
CADR (Clean Air Delivery Rate) measures how many cubic feet of clean air an air purifier produces per minute:
- Small rooms:100-200 CADR (up to 200 sq ft)
- Medium rooms:200-300 CADR (200-400 sq ft)
- Large rooms:300-450 CADR (400-600 sq ft)
- Extra large:450+ CADR (600+ sq ft)
Quick Reference: Common CADR to Room Size
| CADR Rating | 2 ACH Coverage | 4 ACH Coverage | 5 ACH Coverage | Best For |
|---|---|---|---|---|
| 100 CFM | 375 sq ft | 188 sq ft | 150 sq ft | Small bedroom, office |
| 200 CFM | 750 sq ft | 375 sq ft | 300 sq ft | Master bedroom, living room |
| 300 CFM | 1,125 sq ft | 563 sq ft | 450 sq ft | Large living room, open plan |
| 400 CFM | 1,500 sq ft | 750 sq ft | 600 sq ft | Great room, small apartment |
| 500 CFM | 1,875 sq ft | 938 sq ft | 750 sq ft | Whole floor, large space |
* Assumes 8-foot ceiling height. Adjust for different ceiling heights.
Real-World Examples: Popular Air Purifiers
See exactly how many square feet popular air purifier models can clean effectively. We'll analyze real products with their actual CADR ratings to help you understand coverage capabilities.
Levoit Core 300 - Bedroom Specialist
CADR: 141 CFM (Smoke) | Popular compact air purifier
Coverage Analysis:
- Maximum coverage (2 ACH):529 sq ft
- Recommended (4 ACH):264 sq ft
- Allergy relief (5 ACH):211 sq ft
- Medical grade (6 ACH):176 sq ft
Real-World Application:
The Levoit Core 300 is perfect for:
- • Master bedroom: 200-260 sq ft with excellent filtration
- • Home office: 150-200 sq ft for all-day clean air
- • Nursery: Up to 175 sq ft with medical-grade cleaning
- • Studio apartment: 400-500 sq ft with basic filtration
💡 Pro Tip: The Core 300 runs whisper-quiet at 24 dB on low speed. For bedroom use, it can effectively clean a 200 sq ft room while maintaining peaceful sleep conditions.
Coway AP-1512HH Mighty - Living Room Champion
CADR: 246 CFM (Smoke) | Best-selling mid-range purifier
Coverage Analysis:
- Maximum coverage (2 ACH):923 sq ft
- Recommended (4 ACH):461 sq ft
- Allergy relief (5 ACH):369 sq ft
- Medical grade (6 ACH):308 sq ft
Real-World Application:
The Coway AP-1512HH excels in:
- • Living room: 400-450 sq ft with 4-5 ACH
- • Open kitchen/dining: 600-800 sq ft with 3 ACH
- • Large bedroom: 300-350 sq ft with allergy relief
- • Small apartment: 700-900 sq ft with basic coverage
💰 Value Winner: With its 246 CFM CADR and $229 price point, the Coway offers excellent coverage per dollar. It can handle most residential rooms with energy-efficient operation at just 77W.
Honeywell HPA300 - Large Room Powerhouse
CADR: 320 CFM (Smoke) | Commercial-grade performance
Coverage Analysis:
- Maximum coverage (2 ACH):1,200 sq ft
- Recommended (4 ACH):600 sq ft
- Allergy relief (5 ACH):480 sq ft
- Medical grade (6 ACH):400 sq ft
Real-World Application:
The Honeywell HPA300 dominates in:
- • Great room: 500-600 sq ft with excellent cleaning
- • Open floor plan: 800-1000 sq ft with good coverage
- • Basement/garage: Up to 1200 sq ft for basic filtration
- • Commercial space: 400-500 sq ft meeting rooms
⚡ Power Note: The HPA300 consumes 130W on high speed. While powerful, consider energy costs for 24/7 operation. Best used in spaces that need rapid air cleaning or have high pollution.
Blueair Blue Pure 211+ - Silent Performer
CADR: 350 CFM (Smoke) | Ultra-quiet large room coverage
Coverage Analysis:
- Maximum coverage (2 ACH):1,313 sq ft
- Recommended (4 ACH):656 sq ft
- Allergy relief (5 ACH):525 sq ft
- Medical grade (6 ACH):438 sq ft
Real-World Application:
The Blue Pure 211+ is ideal for:
- • Master suite: 500-600 sq ft with whisper operation
- • Yoga/meditation room: 400-500 sq ft ultra-quiet
- • Baby nursery: 300-400 sq ft with silent nights
- • Open loft: 1000+ sq ft with 2-3 ACH coverage
🔇 Quiet Champion: At just 31 dB on low and 56 dB on high, the Blue Pure 211+ delivers 350 CFM while remaining quieter than most 200 CFM units. Perfect for noise-sensitive environments.
IQAir HealthPro Plus - Medical Grade Monster
CADR: 450 CFM (equivalent) | Hospital-grade filtration
Coverage Analysis:
- Maximum coverage (2 ACH):1,688 sq ft
- Recommended (4 ACH):844 sq ft
- Allergy relief (5 ACH):675 sq ft
- Medical grade (6 ACH):563 sq ft
Real-World Application:
The IQAir HealthPro Plus handles:
- • Whole apartment: 800-1000 sq ft with 3-4 ACH
- • Doctor's office: 500-600 sq ft medical-grade
- • Allergy sanctuary: 600-700 sq ft at 5 ACH
- • Chemical sensitivity: 400-500 sq ft maximum filtration
🏥 Medical Grade: The HealthPro Plus uses HyperHEPA filtration capturing particles down to 0.003 microns. While expensive at $899, it provides unmatched filtration for severe allergies, MCS, or medical needs.
Quick Comparison: CADR to Coverage
| Model | CADR | Best Coverage | Price | Best Use |
|---|---|---|---|---|
| Levoit Core 300 | 141 CFM | 264 sq ft | $100 | Bedrooms |
| Coway AP-1512HH | 246 CFM | 461 sq ft | $229 | Living rooms |
| Honeywell HPA300 | 320 CFM | 600 sq ft | $250 | Large rooms |
| Blueair 211+ | 350 CFM | 656 sq ft | $300 | Quiet spaces |
| IQAir HealthPro+ | 450 CFM | 844 sq ft | $899 | Medical needs |
* Best Coverage = 4 ACH with 8-foot ceilings. Actual coverage varies based on room conditions.
Frequently Asked Questions
Q: What if my ceiling height is different than 8 feet?
Use the calculator above to adjust for your actual ceiling height. Higher ceilings mean less coverage area since there's more air volume to clean. For 10-foot ceilings, reduce coverage by about 20%. For 12-foot ceilings, reduce by about 33%.
Q: Should I use the manufacturer's stated room size or calculate my own?
Calculate your own using CADR ratings. Manufacturer room sizes often assume only 2 ACH, which is insufficient for allergies or high pollution. Use our calculator with 4-5 ACH for accurate sizing.
Q: Can I use multiple smaller purifiers instead of one large one?
Yes! Multiple smaller units can be more effective than one large unit. They provide better air distribution and allow zone control. For example, two 200 CFM units can outperform one 400 CFM unit in an L-shaped room or multi-room setup.
Q: How does furniture and room layout affect coverage?
Cluttered rooms or those with poor air circulation need higher CADR. Add 10-20% more CADR for rooms with lots of furniture, curtains, or alcoves. Open floor plans may need strategic placement or multiple units for even coverage.
Q: What's the difference between smoke, dust, and pollen CADR?
Smoke CADR measures the smallest particles (0.1-1 micron), dust covers medium particles (0.5-3 microns), and pollen covers large particles (5-11 microns). Use smoke CADR for general sizing since it's usually the lowest and ensures good performance across all particle sizes.