Best portable humidifier for the whole house

Humidifier test: the best room humidifiers in comparison

Full steam ahead: humidifier under test

03/10/2021, 10:35 AM | by Gunnar Troitsch

Content based on the test results from ÖKO-TEST *

A humidifier prevents dry air, which first affects the eyes and mucous membranes and then the whole body. The individual models work according to three different functional principles. The prices are between 25 and 125 euros. First place went to the Philips Series 2000 HU4811. In the following article we explain the differences and present the winner of the humidifier test. In the video we explain why humidifiers are so important, especially in winter.

This article was created by CHIP authors and is based on the results of the article "Humidifier test: Bacteria in the air" by ÖKO-TEST. The content is based on the print version of the building and living guide from 2019. The full article can be purchased online. The CHIP test center was not involved in the investigation.
You can read that in the article: First, we will present the best humidifiers in an overview and in detail. Then we will give you a price estimate and explain what humidifiers are all about and which types are available. In our purchase advice you can read what is important when buying a humidifier. Finally, you will learn how the humidifier test works.

Humidifier test: The best evaporators at ÖKO-TEST (05/2019)

Test winner & price tipAlternative (evaporator)



Philips Hu 4811/10 Series 2000

Stadler form Oskar

Overall rating

Overall rating

very good

very good

Max. Amount of water dispensed

Max. Amount of water dispensed

139.4 g / h

124.3 g / h

Follow-up costs

Follow-up costs

9.90 euros per replacement filter

36.20 euros for four replacement filters,
19.90 euros for silver ion cubes

Most popular shop

Most popular shop

from 85 €

TO THE SHOP (Amazon)

from 115 €

TO THE SHOP (Amazon)

price comparison

price comparison

Compare prices

Compare prices

Test winner & price tip: Philips Series 2000 HU4811

  • Test winner & price tip: Philips Series 2000 HU4811

    Overall grade: very good Test result practical exam: very good; Test result Other defects: good

Evaporation principle
Night light
Rather low humidification performance
No hygrostat
The Philips HU4811 won the test (see Amazon). The evaporator is quiet and effective at the same time. The technology used ensures that any germs and pathogens do not get into the air. The water evaporates over the large surface of the filter-like fleece. Limescale, dirt and any pathogens are reliably retained.
The device does not have a hygrostat. If you want intelligent control based on the currently measured humidity, you have to resort to a (somewhat more expensive) sister model, such as the HU4814 / 10. The Philips evaporator costs around 85 euros and is therefore in the middle of the test in terms of price.

2nd place: Stadler Form Oskar (for design fans)

  • Stadler form Oskar

    Overall grade: very good Test result practical exam: very good; Test result Other defects: good

Low energy consumption
Rather low humidification performance
The Stadler Form Oskar (view on Amazon) takes second place in the comparison. Like the test winner, it works on the principle of evaporation. According to the provider, the two filter cartridges must be replaced every two to three months. According to the supplier's website, they cost 19.90 euros in a pack of two and 36.20 euros in a pack of four. According to the provider, the “silver cube” for dispensing silver ions should be changed once a year. According to the provider website, it costs 19.90 euros. According to the provider, the maximum amount of water dispensed relates to a room with 25 percent relative humidity and 25 degrees Celsius. ÖKO-TEST had tests carried out in a room with 45 +/- 2 percent relative humidity and 23 +/- 1 degrees Celsius, as prescribed by the DIN 44973 standard.

Further humidifiers in the test

Third place in the test was the Solis Aroma Steamer. The humidifier with an overall rating of "good" is now out of stock (check on Amazon). The other five test devices were ultrasonic atomizers, none of which ÖKO-TEST gave a good rating: three models received a “sufficient” rating, two devices were even “unsatisfactory”.

This is how ÖKO-TEST tests air humidifiers

ÖKO-TEST purchases the test candidates and tests them in a testing institute. The power actually consumed is measured there and it is checked in a climatic chamber under standardized conditions how much water the humidifiers emit per hour. Another laboratory is conducting long-term tests to determine whether the devices introduce mold and / or bacteria into the room air. To do this, the testers measure the germ count in the air in a special chamber after four and eight weeks. During this period, the devices are cleaned strictly in accordance with the operating instructions. In addition, the operating instructions are assessed. Finally, a materials testing laboratory checks the humidifier material for toxic elements such as antimony and chlorinated compounds, which are an environmental problem.

How much do I have to spend on a good humidifier?

In terms of price, humidifiers cover a fairly wide range. You can get simple ultrasonic nebulizers without a hygrostat and other additional features for less than 20 euros. If the humidifier becomes a design object or if it creates a relatively high humidification performance with evaporation technology, the price can quickly reach 200 euros and more. A reasonable and sensible choice can be a device in the mid-price range: Our test winner costs around 85 euros and offers good humidification performance. Unfortunately it lacks a hygrostat. In fact, there is a sister model with hygrostats, which at 130 euros is also more expensive than our test winner.

When do I need a humidifier and when is one not needed?

A certain level of humidity is good for human - and also animal - well-being: Doctors recommend a relative humidity between 40 and 60 percent so that the mucous membranes of the respiratory tract do not dry out. However, especially in winter, it can happen that the humidity in rooms is well below the recommended values. This is because there is absolutely less water vapor in the cold outside air. If you then ventilate the living rooms, this air - low in water vapor - flows in. In the cold air, the relative humidity is usually still right. However, if this air warms up in the room, it decreases "relatively", since warm air can absorb much more water vapor than cold air. This is how the dry room air is created in winter.
A humidifier can help here: It ensures that additional water vapor gets into the room air. Water vapor does not necessarily have to mean that it has to be an evaporator device: Evaporated water is also water vapor. To illustrate: At 0 ° C and 100% humidity, around 4.9 grams of water are dissolved in one cubic meter of air. So if you ventilate your living room (around 60 m³) when the outside temperature is 0 ° C and the weather is foggy, you have 100% relative humidity in the room as long as it is cold. If you close the window, the room and air warm up again. At an air temperature of 10 ° C the relative humidity is 55%, at 20 ° C it is only 26%. To get to a comfortable 55%, 270 ml of water must be brought into the air. A person gives off between 1 and 1.5 liters of water through the air they breathe. Eight people could therefore raise the humidity in this room to a medically good level in one hour. However, then it would probably have to be aired again urgently. For comparison: Our test winner would need around 2 hours to raise the humidity to a comfortable level - without polluting the air quality itself.

Air humidifier types: evaporator, vaporizer or ultrasonic nebulizer?

There are three types of humidifiers in the test, which differ primarily in the technology with which they distribute the moisture in the air. There are surface evaporators, evaporators and ultrasonic devices.
The probably most careful variant of air humidification is used by the Evaporator, which allows the water to evaporate on a huge surface and then blows the humid air into the room via ventilation. In the comparison test, two devices work according to this principle. They cost between 85 and 125 euros, one of which is the Philips HU4811, which costs around 85 euros. The heart of the system is a filter-like insert, which is often perforated and represents a huge evaporation surface. The insert stands in the water, which is literally absorbed by the capillary effect and evaporates on the surface without any additional energy supply. The humid - and cool due to the evaporation - air is then blown into the room with a fan wheel. The fan wheels of the devices in the test are so large that it is almost noiseless in low operating levels. The energy balance of the surface evaporators is also very favorable, they consume between 6.4 and a maximum of 15 watts. In addition, they get by with relatively little care and maintenance. The formation of Legionella is not a problem with this type of humidifier. Rinsing with household descaler, citric acid, or vinegar are effective at removing limescale and other debris.
The second type of humidifier works with heat, which simply evaporates the water. This steam is almost sterile, but boiling water costs a lot of energy. The power consumption of the evaporator devices in the test is between 115.6 and 318.5 watts. Ten hours Evaporator-Operation can therefore cost about one euro. As an often positive side effect, you also heat your apartment at the same time - but there are cheaper methods for doing this. The devices are priced between 100 and 120 euros in the test. For families with small children, but also for adults with respiratory problems, humidifiers such as the Solis Aroma Steamer can be the right choice despite the high operating costs: essential oils can be easily dispersed into the room air with the hot steam. This ensures a clear nose and a peaceful sleep, especially at night. If you have concerns about running a vaporizer in the bedroom at night: Almost all devices switch off automatically when the water is used up. Many even have integrated timers or hygrometers, so that automatic operation is also possible.
Most of the humidifiers on the market work with it Ultrasonic, including the Wick Mini humidifier. This is an energy-saving and very effective way of humidifying the air. The water is set in strong, high-frequency oscillation, which knocks many small water droplets out of the liquid and thus creates a visible, cold mist. Anyone who wants to enrich their room air with moisture quickly and inexpensively is well served with an ultrasonic nebulizer. There are two disadvantages: lime and germs. Such devices emit both of these into the air. The limescale settles within a few meters around the humidifier as a white film of dust on furniture, appliances and the floor; the germs (such as legionella) are transported in the mist until it evaporates. Of course, some humidifiers have built-in limescale filters and of course you can also use distilled water to eliminate the limescale problem. Shorter maintenance and care intervals are still the order of the day with regard to the risk of sprouting germs. Some devices - such as the Rowenta model - also combine ultrasound and vaporizer technology. Since fog still leaves the device, a significant reduction in germs is at least doubtful. The limescale filters used in some models (small spheres on which the limescale should adhere) cannot work wonders either. Even with such a filter, water with a high content of calcium can cause calcium deposits in the vicinity of the device in the long term.

Buying a humidifier: What to look out for when buying a humidifier

Regardless of which type of humidifier you choose: All models are built quite simply and there are only a handful of criteria in addition to the appearance that you should pay attention to when buying.
  • Humidification performance: Depending on the size of the room and the current moisture deficit, you should choose a humidifier that also brings enough water into the air. The way in which the manufacturers specify the humidification performance is not standardized: some give recommended room sizes in m², some also indicate the amount of water in g / h. When specifying square meters, you should assume that the manufacturer is likely to assume an average ceiling height of 2.40 meters. If your rooms are taller, you will likely need a device with a slightly larger square meter than your room actually has. If the manufacturer specifies the evaporation rate in g / h, you can assume that 100 g / h is sufficient for a small room and 300 - 400 g / h can help a large room achieve sufficient humidity.
  • Noise development: The quiet hum of a fan or the subtle humming of the ultrasonic atomizer can become a real problem in the bedroom at night. If in doubt, use a device that has a special night mode.
  • Size of the water tank: Here, a balance must be made between frequent reloading of the container and the potential germ load that may develop. Therefore, bigger is not necessarily better. A tank with a capacity of around 3 liters is a good compromise: with a humidification output of 100 g / h, this is enough for about 30 hours; if the device atomizes 300 g / h, it still runs for 10 hours.
  • Power consumption: Evaporators and ultrasound devices use very little electricity. Evaporators, on the other hand, take a long time into the socket. With current electricity prices of around 30 cents / kWh and a consumption of 350 watts, this adds up to around 1 euro in electricity costs for 10 hours of steam.
  • Risk of burns: There is an increased risk of burns, especially with evaporators, as the escaping water vapor is over 100 ° C. The manufacturers of such devices like to advertise that essential oils can be easily evaporated and they praise the devices for children's rooms. However, you should only operate a vaporizer device in a child's room if you are sure that children cannot reach the device.

The most important questions about humidifiers at a glance

Evaporator, vaporizer or ultrasonic device? What is better?

Ultrasound machines are very efficient. They consume little electricity, create a comparatively large amount of water in the air and, on top of that, are inexpensive to buy. However, there can be problems with limescale deposits and an increased bacterial load. Evaporators use a lot of electricity and are more dangerous than models of other types due to the hot steam. Evaporators require little electricity, have hardly any problems with mold and germs, but lag behind evaporators and ultrasound devices in terms of humidification performance.

Does a hygrostat on the device make sense?

The larger the room, the less important a hygrostat is, as the air humidity rises more slowly here. Conversely, a hygrostat can prevent oversaturation in small rooms.

What does a good humidifier cost?

You can get our test winner for around 85 euros. However, it has a rather low evaporation capacity, so you should use another model or two devices in larger rooms. The energy costs are kept within limits - with the exception of evaporator devices.

Can I use distilled water in the humidifier?

In fact, using distilled water has some advantages: On the one hand, you do not need to descale the device, and on the other hand, it also reduces the risk of increased bacterial load. However, to be on the safe side, read the manual for your device.

Where is the best place to set up my humidifier in the room?

In general, it is an advantage if the humidifier is free-standing and the moist air does not hit walls or furniture directly. Especially with models that work with ultrasound, you should make sure that no precipitate forms around the device that could damage furniture or parquet.

Advice and practical tips on humidifiers