Humidifier VS Dehumidifier: Which One Do I Need?

Confused about the functionality of humidifier and dehumidifier, you're not alone. Both might sound the same and has to do with humidity control, it is actually the opposite of each other. In this post, I'm going to clear the air between these two and answer the most asked questions of all: Which ONE do I need. I'm also addressing a series of common queries gathered throughout the five years here. Some questions you might think is silly, but trust me, is been asked far too many times.
Short answer
Humidifier adds moisture. Dehumidifier drains moisture.


The Differences Between Humidifier and Dehumidifier



Typically compact in size unless it is an air purifier humidifier combination.Besides the renewable version, most dehumidifiers have medium to large body with a removable water tank.
Increase the room humidity level.Decrease the room humidity level.
Health Benefits
Moisture skin and improve breathability.Stop allergic symptoms like chronic sneezing, coughing headache.
Best Used
Bedroom, bathroom, living hall, and winter season where humidity is low.Basement, living hall, places with musty smell, and summer where humidity is high.
• Evaporative  • Steam vaporizer/ Mist  • Ultrasonic  • Impeller• Mechanical or refrigeration  • Absorption/ Electronic desiccant  • Thermoelectric  • Ionic membrane
Target Group
Suitable for all. Folks with children need to be cautious on the heat produced by the warm-mist humidifier.All including baby, children, adult, and elderly that would be at risk of mold infection.
Noise Level
Subtle to soft for ultrasonic, cool mist. Livable white noise for impeller, warm mist (steam).Louder but manageable noise level depending on the selected speed and placement.
Cost with Upkeeping
Cheap for a compact vaporizer/ cool mist between $20-50. Expect price from $100 all the way to $500 for 2-in-1 air purifier humidifier combo.Mini/ portable unit is at an affordable price of $30-50. Expect price between $100-300 for a full-sized 30-70 pint dehumidifier.

Do I Need a Humidifier Or a Dehumidifier?

Get a humidifier if your room humidity level falls below 30% or the air is stale and dry e.g. in the winter. If you often fall sick from virus infection, humidifier can stop the spread. Get a dehumidifier if humidity level goes beyond 50% or the air is humid e.g. in the summer. Consider one if your house is constantly infested with mold. Ideally, the sweet spot is between 30-50% humidity level. Achievable but you will have to swap the machine during season change.

Too technical? No problem. You can also rely on your allergies to determine what is needed. If one is experiencing the following symptoms:

  • Itchy or flaky skin
  • Chapped lips
  • Dry or nose bleeds
  • Dry cough
  • Dry eyes
  • Breathing difficulty
  • Static shock

Humidifier it is. Start using a dehumidifier if you experience the following signs:

  • Stuffy or runny nose
  • Postnasal drip coughing
  • Bloodshot or watery eyes
  • Dry throat
  • Itchiness all over the body
  • Headache or dizziness
  • Wheezing or shortness of breath
  • Static shock (again)

My take? Skip the second option as most symptoms are repetitive and can be caused by any allergies. Instead, get a hygrometer/ humidity meter for less than 10 bucks and you will have a clear answer.

In an ideal situation, humidity in a room would fall between the recommended 30 to 50 percent. In real-life, humidity is a climate variable that can be affected by many external factors. Weather for one (heatwave/ rainfall), season (summer/ winter), and also location (country/ state). Human activities such as mining, deforestation also play a big part in the humidity of an area. While it's impossible for us to stop climate change or the destruction of forests, all hope is not lost. We can still protect ourselves in the sanctuary of our home. These two FABULOUS machines are designed to do just that.

Humidifier VS Dehumidifier

Let's go through key differences. Humidifier adds moisture into the air through the release of cool or warm mist. Dehumidifier would bring the humidity level down by absorbing moisture from the air. At the end of the day, Humidifier reservoir will be empty through water dispersion. Dehumidifier water reservoir will be full through water collection. Humidifier is best used to keep skin hydrated, clear nasal passage airways, alleviate dry cough, and throat irritation. Dehumidifier is best used to halt microorganisms like mold from growth. This would curb down symptoms like sinus, red eyes, cough, itchiness, and headache. Popular spot for a humidifier is bedroom; dehumidifier is often placed in the basement due to poor ventilation. Noise level favors more to the former than the later traditional refrigeration or desiccant mechanism.

You can find humidifier in evaporative form, steam vaporizer (cold & warm mist), ultrasonic, or impeller. Whereas for dehumidifier mechanical, refrigeration, absorption/ electronic desiccant, thermoelectric, or ionic membrane. Lastly, a humidifier is generally cheaper but costlier to maintain if you account for the essential oil add-ons (optional). Dehumidifier on the other hand, is more expensive but with zero maintenance cost if no replaceable filter is involved.

Frequently Asked Questions FAQ

Humidifier or Dehumidifier for Stuffy Nose/ Cold

Humidifier as added moisture from cold or warm mist can relieve a sinus problem. Stuffy nose happens when your nasal passage is blocked by excessive mucus. This will lead to breathing difficulty and nasal/ sinus infection. Incorrect use of a dehumidifier will cause the air drier and thicken the mucus.

Humidifier or Dehumidifier for Cough

Humidifier is ideal to reduce cough as it adds moisture into the air. Dry air can cause cold, throat irritation, and chest tightness. The thickens mucus will create post-nasal drip which then leads to chronic cough. Dehumidifier help alleviates respiratory symptoms including cough but the impact is less significant.

Humidifier vs Dehumidifier for Baby

Your little one has a much narrower nasal passage that is sensitive to any congestion. Humidifier creates an optimal breathing environment for the baby especially during winter. The added moisture reduces air dryness thus less mucus obstruction. Dehumidifier protects the baby with developing immune system from mold, bacteria and virus attack. Without excess moisture, the microbes will not thrive and less are spread across the home. In short, both humidifier and dehumidifier will benefit babies through humidity management.

Humidifier or Dehumidifier for Asthma

Dehumidifier is more common for an asthmatic person as it removes respiratory ailments. An asthma attack happens when the lining of the airways also becomes swollen and air cannot pass through. The allergic reaction triggered when one is exposed to microbes like mold or germ. Dehumidifier cut away the microorganisms food source thus effectively killing them off. A humidifier can help ease nasal congestion and improve breathing quality.


Max Fernandez

Growing up in New Orleans, one of the highest relative humidity in the United States, Max knows a thing or two about humidity. Besides reviewing dehumidifiers for living, you will find him gyming in the basement.