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Home dehumidifier calculation/ sizing/ capacity selection.

Discover the power of a home dehumidifier calculator, a valuable tool that helps you determine the perfect dehumidifier size for your home, ensuring optimal humidity control and a comfortable living environment.


And that's where the correct dehumidifier capacity calculation comes in. This calculator simplifies your life and helps you bid goodbye to excess humidity by accurately determining the ideal dehumidifier size for your home. Say hello to a more comfortable home with the assistance of the Home Dehumidifier Calculator...

By inputting specific details about your living space, such as dimensions and current humidity levels, the Home dehumidifier size calculator generates accurate recommendations for the ideal dehumidification system capacity. You are no more guessing or relying on estimations. This tool makes the process precise, ensuring you choose the suitable dryer for optimal moisture control.

But what makes the home dehumidifier Calculator so unique? It simplifies your life in several ways. Firstly, accurate sizing. By providing precise recommendations, the calculator saves you the hassle of selecting the wrong size. Say goodbye to ineffective moisture control and hello to a dehumidifier that genuinely meets your home's needs.

To understand this calculator, we will take one example. Let's calculate the capacity for a room of 10 meters in length, 5 meters in Width, and 3 meters in height. Current & desired humidity is 80 & 50%RH, respectively, with a room temperature of 22 deg Celsius.
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Dehumidifier design calculation software for selecting the right capacity

Parameter Value
Room temperature (°C) °C
Room size (M) M
Present Relative Humidity (RH%) RH
Absolute Humidity (GRAM/M³) GRAM/M³
Desired Relative Humidity (RH%) RH
Absolute Humidity (GRAM/M³) GRAM/M³

Disclaimer: The online calculator is provided for illustrative purposes only, and the information obtained by using the online calculator is not, and should not be taken as, technical advice to any person or company. Results may vary depending on the accuracy and comprehensiveness of the information you provide while using the online calculator. The online calculator is not a substitute for consulting a qualified professional. We Control Technologies FZE accepts no liability whatsoever for any losses or liabilities allegedly arising from the use of the online calculator by any person or company.

Relative humidity 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
temperature °C
+35 4.0 7.9 11.9 15.8 19.8 23.8 27.7 31.7 35.6 39.6
-2 +8 +14 +18 +21 +25 +28 +31 +33 +35
+30 3.0 6.1 9.1 12.1 15.2 18.2 21.3 24.3 27.3 30.4
-6 +3 +10 +14 +18 +21 +24 +26 +28 +30
+25 2.3 4.6 6.9 9.2 11.5 13.8 16.1 18.4 20.7 23.0
-8 0 +5 +10 +13 +16 +19 +21 +23 +25
+20 1.7 3.5 5.2 6.9 8.7 10.4 12.1 13.8 15.6 17.3
-12 -4 +1 +5 +9 +12 +14 +16 +18 +20
+15 1.3 2.6 3.9 5.1 6.4 7.7 9.0 10.3 11.5 12.8
-16 -7 -3 +1 +4 +7 +9 +11 +13 +15
+10 0.9 1.9 2.8 3.8 4.7 5.6 6.6 7.5 8.5 9.4
-19 -11 -7 -3 0 +1 +4 +6 +8 +10

How to do home dehumidifier calculation?

Step 1 - insert the room temperature

First, insert the temperature value in the room in Degrees Celsius (°C). Use a digital thermometer to major it, or you can check the temperature setting of your air conditioner. Generally, a warm room needs a lower dehumidifier capacity than a colder room of the same size.

In our example, it is 22 °C.

Step 2- insert room dimentions in dehumidifier calculator

Mention the room's length, Width, and height that must be dehumidified in meters. Use a laser meter to measure wall-to-wall length and Width. In the case of an irregular shape room, consider the dimensions of larger sides. In the case of a nonflat roof, consider average height.

In our case, length = 10 meters, Width = 5 meters, and height is 3 meters.

Step 3 - Desired and current humidity level

Insert the value of current & desired humidity in the bedroom in %RH. To measure present moisture, you can use a digital hygrometer which you can get from any tool shop. Many air conditioner controllers also show the room humidity on their display. Desired moisture level we know.

In our case, insert Present Relative Humidity (%RH) = 80

Desired Relative Humidity (%RH) = 50

Step 4 - Find out absolute humidity at current RH

Please refer to the table to find the absolute humidity value in g/m3 for a room temperature and current humidity level. For example, for a room temperature of 22 °C and current humidity of 80 %RH, the absolute humidity is 13.8 g/m3. Please note that 22 °C is not available in the table to consider previous lower temperatures, i.e. 20 °C

Insert, Present Absolute humidity level (Gram/m3) = 13.8

Step 4 - Find out absolute humidity at desired RH

From the table, find the absolute humidity value in g/m3 corresponding to the desired humidity and room temperature. For example, for a room temperature of 22 °C and desired humidity of 50 %RH, the absolute humidity is 8.7 g/m3. Please note that 22 °C is not available in the table to consider previous lower temperatures, i.e. 20 °C

Insert, Desired Absolute humidity level (Gram/m3) = 8.7

Step 6 - dehumidifier calculation and result

Click the "Click here for Dehumidifier Result" button to get Liters per day dehumidifier capacity. Please note that you might get some random ratings. Always choose an immediate next larger-size dehumidifier available in the market. For example, for 18.36 liters/day, you can select a unit with 40 or 50 liters daily.

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Frequently asked questions.

Yes, a home dehumidifier calculator is specifically designed to take into consideration a wide range of factors and suggest you an ideal moisture extraction capacity against which you can choose your dehumidification units easily!

These calculators consider various factors such as the room dimensions, moisture levels, and the desired humidity range. By inputting these details into the calculator, it generates a recommendation for the ideal dehumidifier capacity that will effectively remove excess moisture from your space.

Whether you require effective moisture management for a single room, kitchen, bathroom, or even the whole house, a home dehumidifier capacity calculator can guide you to selecting the best unit that aligns with your requirements. Please use our other resources for dehumidifier maintenance & reviews.

While a home dehumidifier sizing calculator primarily focuses on factors such as room size and moisture levels, it typically does not directly consider the number of occupants within the room.

The primary reason for this omission is that the moisture generated by human occupants is relatively minimal compared to other moisture sources like cooking, bathing, or humidity intrusion from the outside environment.

However, it's worth noting that if you have a high number of occupants in a confined space, it may lead to increased humidity levels due to breathing and perspiration and might require a unit with a higher humidity removal capacity.

In such cases, it's advisable to consider a slightly larger dehumidifier capacity to compensate for the additional moisture generated by human activity.

While home dehumidifier calculators are valuable tools for determining the appropriate dehumidifier capacity, they may not account for certain specific factors that could influence your decision.

For example, the calculator typically does not consider the presence of water leaks, excessive condensation on windows, or the specific humidity requirements of sensitive materials like musical instruments, artwork, or electronics.

It's essential to be mindful of these additional considerations and factors that may require you to adjust the recommended dehumidifier capacity accordingly. It's always a good idea to consult with a professional or the manufacturer's guidelines to ensure you make an informed decision.

Yes, indeed! A home dehumidifier calculation tool often takes into account factors such as temperature and airflow in the room when providing recommendations for the appropriate dehumidifier capacity.

Temperature plays a crucial role in the dehumidification process, as warmer air can hold more moisture compared to cooler air. Additionally, airflow affects the distribution of moisture within a room.

A stagnant or poorly ventilated space may benefit from a more powerful dehumidifier to ensure efficient air circulation and moisture removal.

By considering these factors, a home dehumidifier calculation tool aims to offer you a tailored recommendation that suits your specific environment and helps you achieve optimal humidity levels.