Dehumidifier Size Calculator
Pint capacity for your room size and dampness level.
Enter your values
Enter the room area in sq ft.
Choose one of: Slightly damp — musty smell, Moderately damp — damp smell, Very damp — damp spots on walls, Wet — sweating walls, standing water.
Enter the ceiling height in ft.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- Recommended capacity
- 30 pints/day
- Model size to buy
- 30-pint
- Room volume
- 8,000 cu ft
- Drainage
- Bucket emptying is fine
Quick answer
Under DOE 2019 rules a moderately damp 1,000 sq ft room needs about a 25-pint dehumidifier; add 5 pints for every step wetter.
pints = base for area + dampness adjustment
At a glance
| What it does | Pint capacity for your room size and dampness level. |
|---|---|
| Category | Home & DIY |
| Inputs needed | Room area, Dampness level, Ceiling height |
| Main output | Recommended capacity |
| Formula | pints = base for area + dampness adjustment |
| Cost | Free — no sign-up, no download |
How to use the Dehumidifier Size Calculator
- 1Measure the room's square footage.
- 2Pick how damp the space feels or smells.
- 3Adjust the ceiling height if it isn't 8 ft.
Inputs explained
- Room area(sq ft)
- Enter the room area in sq ft.
- Dampness level
- Choose one of: Slightly damp — musty smell, Moderately damp — damp smell, Very damp — damp spots on walls, Wet — sweating walls, standing water.
- Ceiling height(ft)
- Enter the ceiling height in ft.
Worked example
Using the values the calculator loads with:
Inputs
- Room area1000 sq ft
- Dampness levelModerately damp — damp smell
- Ceiling height8 ft
Results
- Recommended capacity30 pints/day
- Model size to buy30-pint
- Room volume8,000 cu ft
- DrainageBucket emptying is fine
Frequently asked questions
What size dehumidifier for a 1000 sq ft basement?
A 30-pint unit for moderate damp, or 40–50 pints if the walls sweat or there's standing water.
Why did pint ratings change?
DOE retested at 65 °F in 2019, so a modern 30-pint unit removes as much as an old 50-pint model.
What do I need to enter into the Dehumidifier Size Calculator?
Just 3 values: room area, dampness level, ceiling height. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the Dehumidifier Size Calculator work out the answer?
Under DOE 2019 rules a moderately damp 1,000 sq ft room needs about a 25-pint dehumidifier; add 5 pints for every step wetter. It applies the formula pints = base for area + dampness adjustment and shows the working so you can check each step by hand.
Is the Dehumidifier Size Calculator free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.