Dehumidifier sizing calculator25 pints/day
Choose capacity from your room size and dampness using current ENERGY STAR pint ratings.
Your starting point
25 pints/day
Planning range
20–30 pints/day
A screening estimate under the assumptions below. The range is a shopping guide, not a guarantee.
Planning estimate. A licensed contractor must confirm the final size, installation and local code requirements. Electrical work needs a licensed electrician.
Adjust your home
The calculation, step by step.
Current ENERGY STAR room-size and dampness guidance, using modern portable-dehumidifier test ratings.
| Input or step | Calculated amount |
|---|---|
| Area | 1,500 sq ft |
| Dampness | damp |
| Capacity band | 20-30 pints/day |
What moves this number?
Dampness
Persistent condensation needs more capacity than intermittent mustiness.
Area
2,000 sq ft and above uses the larger-room guidance.
Drainage and temperature
Check operating temperature and use a reliable drain for continuous collection.
Your location and assumptions.
Location does not change this model. The selected appliance loads, room conditions or peak usage determine the result.
- For large rooms, ENERGY STAR publishes a minimum (30+, 40+ or 50+); our upper shopping-band limits are assumptions.
- Ratings use the modern approximately 65 F portable test, not the old 80 F AHAM table.
- Exactly 2,000 sq ft is conservatively treated as a large room.
What might it cost to run?
Use nameplate watts ÷ 1,000 × operating hours × your tariff. Pint capacity alone does not specify power or how often the compressor runs. Uses the published 2024 EIA Texas residential average of $0.1494/kWh, not your current tariff.
Before you choose equipment.
Repair leaks and moisture entry first. Standing water and major seepage need building repairs; a dehumidifier alone is insufficient.
Bring this calculation to your installer. They will check the measured load, manufacturer performance, distribution or connections, installation conditions and local requirements.
A few more sizing questions.
What size dehumidifier for 1,500 square feet?
The default screen gives 25 pints/day, with a planning range of 20–30 pints/day. Change the inputs above to reflect your actual home. The selected condition is damp.
Are older AHAM pint ratings comparable?
Older portable ratings commonly used warmer test conditions. We use the current ENERGY STAR guidance and approximately 65°F portable ratings, without mixing old 80°F capacities.
Why is the large-room answer a minimum?
ENERGY STAR gives 30+, 40+ or 50+ pints/day for larger rooms. Our upper band of 30 pints/day is a shopping assumption, not an official maximum.
Will a dehumidifier fix water entering the basement?
No. Repair leaks, drainage and moisture entry. Major seepage or standing water needs a building professional before relying on humidity equipment.
Does operating temperature matter?
Yes. Verify the manufacturer operating range and low-temperature performance. Drain routing and collection capacity also affect whether the unit can run continuously.
Is this a final equipment size?
No. A licensed contractor must measure your building or actual loads, check manufacturer performance and local code, and confirm the final selection.