What Is a Dehumidifier Size Calculator?
A dehumidifier size calculator is a tool that recommends the correct 'Pint Capacity' for a dehumidifier based on your room's size and its moisture level. Choosing the right size is critical for the unit to work effectively and efficiently, preventing mold, mildew, and musty odors in spaces like basements. This free calculator simplifies the selection process to ensure you buy the right unit for your needs.
Last updated: November 8, 2025
How to Use the Dehumidifier Calculator
Our free dehumidifier calculator provides an instant size recommendation. Follow these steps:
- Enter Room Area: Input the square footage of the room you need to dehumidify.
- Select Room Condition: Choose the description that best matches your space (from moderately damp to wet).
- Add Target Humidity (Optional): Enter your desired humidity level (45-50% is ideal for most homes).
- Click "Calculate Size": Get your instant recommendation for the required pint capacity.
Understanding Your Dehumidifier Recommendation
The calculator recommends a 'Pint Capacity,' which indicates how many pints of moisture the unit can remove from the air in 24 hours. The most confusing part of buying a dehumidifier today is the change in sizing standards. Our calculator provides two numbers to help you shop smart:
- For units made AFTER 2019: Use this as your primary number. This is the modern DOE rating tested at 65°F.
- For units made BEFORE 2019: This is an equivalent rating for older models tested at 80°F. A new 35-pint unit is roughly equivalent to an old 50-pint unit.
According to the EPA, maintaining indoor humidity below 60% is key to preventing mold growth. A properly sized dehumidifier is your best tool for achieving this.
Example Dehumidifier Size Calculation
Here is a common scenario for a typical basement.
| Input | Example Value |
|---|---|
| Room Area | 1,500 sq ft |
| Room Condition | Very Damp |
| Recommended Size (2019+) | 35 Pints/Day |
| Equivalent Size (Pre-2019) | ~50 Pints/Day |