What Size of Dehumidifier Do I Need? – 2020 Informational Guide


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We often hear experts say how important it is to maintain humidity levels in our homes, as dry air can cause difficulty in breathing and create a number of different health problems. Also, too much humidity can also lead to serious health problems including allergy problems, growth and inhalation of mold and mildew, and discoloration of your home’s walls.  

What you need is a good quality dehumidifier if your home or certain rooms are affected by moisture or dampness. But before investing in one, it is important to determine how large or small a unit you require. Not only are there different brands and varieties to choose from, they also differ in size and capacity.

In this article, we will list the important qualities in a dehumidifier and help you learn how to choose the right size for your room. In the end, we also provide a review of our favorite dehumidifiers to help you choose the one best for you.

Dehumidifier Size Calculator

Use the calculator below to find the estimated correct size in pints for your dehumidifier:

How to Choose the Correct Size of Dehumidifier

The size of a dehumidifier does not mean its weight or how tall it is but how many pints of water it is able to pull from the air in one day. Dehumidifiers able to remove more moisture in one day tend to be larger in size and take up more space, while smaller units remove less moisture. However, when we talk about the size, we are referring to how much work it can do. There are several factors that determine the right size for your room:

Pint Capacity of a Dehumidifier

Pint capacity is the amount of moisture a dehumidifier is able to remove from an area within a 24-hour period. A dehumidifier’s performance is greatly affected by both the size and humidity level of a particular area. Usually, a dehumidifier with a pint capacity of 70 or less is best for residential use, while those over 70 pints are perfect for industrial or commercial use.   

Size of the Room

Measure the area where you want to operate the dehumidifier. To find out the size of your room in square feet, use a tape measure. Measure the length and width of a room and multiply them. For example, a room that is 50 feet long and 30 feet wide has a total of 1500 square feet (50 x 30 = 1500).

30-Pint Dehumidifier - This is the size considered ideal for areas up to 1500 square feet irrespective of how damp the area is. Thus, these dehumidifiers are appropriate for most residential basements. However, they are also recommended for areas up to 2000 square feet, given that they are not more than moderately damp. These are areas that feel damp and smell slightly musty when the weather is humid, but not all the time.  

40 or 50-Pint Dehumidifier - This size of dehumidifier is recommended for areas up to 2000 square feet that smell musty and feel damp all the time. These are places where you have experienced mold growth in the past or where moisture is visible on the walls.

60 or 70-Pint Dehumidifier - Recommended for spaces larger than 2000 square feet, these dehumidifiers are for extremely wet spaces where there is standing water on the floor.   

Most dehumidifiers are designed with a bucket that collects water and has to be emptied periodically, while there are some models that drain water automatically. These models are best for basements, as floor drains are usually already installed.

Although large dehumidifiers are more expensive, you can save money in the long run by choosing a unit with a higher capacity than needed. A larger capacity unit will not have to work as hard to keep the room dry as a dehumidifier that is recommended according to the size of the room.

Number of People and Pets

Animals and humans expel water through various crevices on their bodies. We can increase the level of humidity of a room, albeit very slightly, just by sneezing, talking, coughing, breathing, and wheezing. For every four to five people you should add five pints to your calculations.


Bathrooms attract bacteria and mold more than any other room. Washing your hands, running steamy showers, and flushing the toilet all increase the RH level of your bathroom. For a bathroom dehumidifier, it is best to add five to ten pints to your calculations.

Choose a Desiccant Dehumidifier for a Cooler Environment

There are two basic types of dehumidifiers: desiccant and refrigerant. Although desiccant dehumidifiers have lower capacity ratings, they are more efficient in lower temperatures than refrigerant dehumidifiers. Therefore, it is best to use such units where temperatures fall below 65 degrees Fahrenheit (18 degrees Celsius). Also, desiccant dehumidifiers are quieter than refrigerant models.

Pick a Refrigerant Dehumidifier for a Hot and Humid Space

If you experience very hot and humid temperatures, a refrigerant dehumidifier will best suit your needs. They have a higher capacity rating and are more suited to higher temperatures due to their efficiency. If you operate your refrigerant dehumidifier in temperatures below 65 degrees Fahrenheit, frost may form on the evaporator coils, thus disrupting the proper functioning of this unit.

Comparison Chart of our Favorite Dehumidifiers


Our Rating


Danby Energy Star 70-Pint Dehumidifier

Danby Energy Star 70-Pint Dehumidifier

Best Overall

Afloia Portable Electric Dehumidifier

Afloia Portable Electric Dehumidifier for Home 2000ML Water Tank, Home Dehumidifier for Bathroom Dehumidifier for Basement Space Bedroom Kitchen Caravan Office Basement Bedroom Bathroom

Best for the Money

Types of Dehumidifiers

Dehumidifiers can be classified into four types according to the way they work. Most of these dehumidifiers range from 15 to 60 pints and maintain 60% relative humidity level.

Heat Pump Dehumidifier

This pump uses a fan, heat exchange coils, and a heat pump to eliminate moisture. The heat pump draws indoor air through the heat exchange coil and the fan. Usually, the coil is at a freezing temperature. However, if collected moisture condenses, it is reheated by another heat coil and then dispersed into space again.

Dehumidifying Ventilators

These dehumidifiers are considered perfect air appliances for attics, basements, and some crawlspaces. They have an exhaust fan and a sensor which work together to create appropriate humidity levels.

Chemical Absorbent Dehumidifiers

These dehumidifiers consist of desiccant-type silica gel and absorbents. This heats the gel and fixes it to a wheel while a separate loop helps to keep the loop dry. The humid air is then expelled via an external vent.

Homemade Dehumidifiers

These simple dehumidifiers can be made with the help of de-icing salt as it works to extract dampness from the air. This water then collects in a bucket placed below. However, it is essential to replace the salt regularly to maintain its effectiveness.

Review of our Favorite Dehumidifiers

Below is a quick overview of the best overall and best for the money options:

Danby Energy Star 70-Pint Dehumidifier


  • Has a Noise Level of 50 Decibels
  • Auto Shut-Off When the Water Container is Full
  • Casters and Side Handles Make it Highly Portable
  • Timer Helps to Conserve Power and Match the Needs of Your Room
  • Energy-Star Qualified Means You Can Enjoy the Efficient, Money-Saving Operation
  • Ideal for Controlling Humidity in Basements and Large Rooms up to 4,500 Square Feet
  • Washable Air Filter Easily Removes Dust and Allergens, Thus Ensuring Efficient Operation
  • Auto Restart Function Ensures the Dehumidifier Resumes Function Once Power is Restored


  • Bucket Has to Be Emptied Manually Due to Lack of Drain Pump

Our Review

The Danby Energy Star 70-pint dehumidifier effortlessly eliminates damaging humidity in large spaces and basements of up to 4,500 square feet. It features an exterior that is compact and sleek and is able to remove 70 pints of excess moisture every day.

It's Smart Dehumidifying technology makes it very easy to maintain healthy humidity in a space. This feature analyzes the ambient temperature of your space and automatically programs the most favorable humidity level. The system also chooses the best fan speed to maintain the set humidity.

This dehumidifier has a fully-loaded electronic panel that allows you to control the operation according to your requirements. Electronic push buttons help you select normal or turbo fan speed, set a humidity level, activate the 24-hour on/off timer, and stay informed of the current humidity conditions. Moreover, the easy-to-read indicator lights let you know when it is time to empty the water tank or when the de-icing mode has activated.

Bottom Line

The Danby Dehumidifier offers a perfect solution to safeguard not only your home but your health as well with this great portable appliance. Its Energy Star rating and environmentally-friendly R410a refrigerant help cut your electricity bill and prevent damage to the ozone layer.

The electronic digital control panel allows you to adjust between two fan speeds while the de-icing feature keeps the internal coils ice-free. Moreover, this unit comes with a two-year warranty that further ensures peace of mind for consumers.

Afloia Portable Electric Dehumidifier for Home 2000ML Water Tank, Home Dehumidifier for Bathroom Dehumidifier for Basement Space Bedroom Kitchen Caravan Office Basement Bedroom Bathroom


  • Portable Design and Easy to Carry
  • White Color Looks Very Chic and Elegant
  • Ideal for Small Rooms or Poorly Ventilated Areas
  • Simple One Button Control is Easy and Convenient
  • Does Not Waste Electricity or Harm the Ozone Layer
  • Ultra-Quiet Peltier Technology Ensures Very Little Noise
  • Auto-Off and LED Indicator to Show When Water Tank is Full
  • 2-Year Warranty Provides Customers Assurance of High Quality


  • Small Size Makes it Ineffective for Larger Spaces

Our Review

The Afloia Portable Electric Dehumidifier is designed with innovative and whisper-quiet Peltier technology that quickly removes moisture from the air around you. It can reduce humidity from any part of your home, thus preventing moisture damage and providing greater comfort for your life. It is also easy to carry from one room to another. Moreover, you can keep it anywhere as it does not take up much space.

It is a very quiet appliance with noise below 42 dB, thus ensuring quiet and sound sleeping. Its large water tank has a maximum capacity of two liters while the auto shut-off feature prevents an overflow of collected water once the reservoir is full. You can easily remove the front water tank and empty it. The dehumidifier will resume working again once you put the empty water tank back in.

The Afloia is powered by an AC cable and perfectly controls condensation and moisture. It is perfect for small spaces such as the bathroom, living room, office, etc. This energy saving and eco-friendly unit is an ideal solution to your mold and mildew problems.

Bottom Line

The Afloia Portable Electric Dehumidifier is an innovative and quiet appliance perfect for small places. It's one button control makes it very easy to operate, while the auto shut-off function ensures no water spillage.


A dehumidifier is a great device that gets rid of the moisture in the air around you and safeguards your clothes and electrical appliances against moisture damage. It helps create a healthy environment for people with breathing allergies and problems.

However, it is essential to get the right size dehumidifier so that you can get the maximum benefit from it. Make sure that you take the above-mentioned considerations into account while calculating the size of the dehumidifier that will be perfect for your living space.