Kelvin and Colour Temperature: Which Light Colour Suits Which Room?
The Colour Temperature: Everything You Need to Know About Choosing the Right Light Colour
Whether a room feels cosy or functional depends not only on the light fitting but above all on the light colour. It is given in Kelvin and describes whether the light appears warm white, neutral white or daylight white. This guide explains what colour temperature means, which Kelvin value suits which room and how you can set or change the colour temperature of your lamps. From the living room to the desk, you will also find out which light colour fits your lighting plan.
What does Kelvin mean in colour temperature?
Kelvin (K) is the unit of colour temperature. It indicates the colour of the light emitted by a light source and says nothing about how hot the lamp gets. A low value such as 2,700 K stands for yellowish-white light reminiscent of incandescent light. A high value such as 6,500 K stands for bluish-white light, similar to daylight on an overcast day.
The scale is based on an idealised glowing body. Depending on its temperature, it emits radiation in a different colour: first reddish, then yellow and finally bluish-white. The colour temperature of a lamp corresponds to the temperature at which this body shows the same light colour. The unit is named after the physicist William Thomson, better known as Lord Kelvin. In photography, the unit mired is also used; a mired value is the reciprocal of the colour temperature. You do not need it to choose a lamp, as packaging and product pages usually state Kelvin.
What colour temperature do common light sources have?
Familiar light sources help to put colour temperature into context. Candlelight is around 1,500 Kelvin, a classic incandescent bulb around 2,700 Kelvin. Daylight varies over the course of the day: at midday the colour temperature is 5,500 to 5,800 Kelvin, an overcast sky reaches 6,500 to 7,500 Kelvin. The colour temperature of daylight is therefore not a fixed number; it changes with the time of day and the weather. This is exactly what lamps with adjustable light colour imitate.
Are colour temperature, light colour and light temperature the same?
In everyday use, all three terms mean the same thing. Colour temperature is the technical term and is measured in Kelvin. Light colour describes the same property in words such as warm white or neutral white. Light temperature is the colloquial variant. Product pages therefore often show both side by side, for example “Light colour: 3,000 Kelvin (warm white)”. The number gives the colour temperature, the word next to it the light colour.
Which Kelvin value corresponds to warm white, neutral white and daylight white?
The common classification distinguishes three light colours. Manufacturers draw the boundaries slightly differently; the table shows the usual values.
| Light colour | Kelvin range | Effect | Typical rooms |
|---|---|---|---|
| Warm white | up to approx. 3,300 K | Cosy, relaxing, reminiscent of candlelight | Living room, bedroom, children’s room |
| Neutral white | approx. 3,300 to 5,300 K | Functional, balanced, without a yellow or blue tint | Kitchen, bathroom, hallway |
| Daylight white (cool white) | from approx. 5,300 K | Cool, bright, activating | Study, office, workshop |
Warm white light has a high proportion of red and therefore feels comfortable. It emphasises the colours of wood and textiles and makes living areas feel homely. This light colour is suitable wherever you want to switch off and relax. For the same reason, warm white light creates an inviting atmosphere in restaurants and hotels.
Neutral white light contains red and blue components in a balanced ratio. It appears brighter and more functional than warm white light without being harsh. Colours and details are easy to see, which makes neutral white light the choice for areas where you work.
Daylight white light has a high proportion of blue and resembles the light of an overcast day. Cool white light feels clear and alert. It suits places where concentration is needed and complements daylight in bright rooms. Rule of thumb: the more active the task, the higher the Kelvin value can be.
What is the difference between Kelvin and lumen?
Kelvin describes the colour of the light, lumen (lm) the quantity. The lumen value indicates how much light a light source emits and is therefore a measure of brightness. A bulb with 3,000 K can be very bright or very dim, depending on its lumen value. Likewise, there are cool white bulbs with low light output. When buying, both values count: Kelvin for the colour impression, lumen for the light intensity in the room. In the room, what counts is the sum of several lights.
Is cool white light brighter than warm white light?
Cool white light appears brighter, but it is not automatically so. Brightness is determined by the lumen value. Many people perceive cool light as clearer and brighter. A warm white bulb with high light output illuminates a room more brightly than a cool white bulb with a low value. Always compare both values.
How does colour temperature influence mood and atmosphere?
Lighting shapes the atmosphere of a room, and colour temperature determines its character. Warm white promotes relaxation and a calm mood. Neutral white creates a clear, friendly effect without being activating. Daylight white has an invigorating effect and is considered to aid concentration. Colour temperature is therefore a decision about effect and well-being and depends on use and personal taste. Before buying, consider whether a room is meant for relaxing or for working.
Which colour temperature suits which room?
The right light colour depends on how the room is used. You will find an overview of suitable lights in the Interior lights category.
Living room: Which light colour creates atmosphere?
In the living room you relax, read, play and celebrate. Warm white light around 3,000 Kelvin creates the cosy atmosphere for this. Neutral white light feels more functional in the living room and suits areas where you are active. A homely living room is created by several light sources that together produce a relaxing atmosphere. Four tips help with planning:
- Choose warm white for the general lighting in the living room.
- Add extra light sources with neutral white light at the reading spot or games table.
- Use dimmable models to adapt light intensity and mood to the evening.
- Distribute the lighting evenly so that no harsh shadows are cast.
You will find suitable models under Living & dining room.
Bedroom: Which light colour helps you fall asleep?
In the bedroom, rest comes first. The colour temperature in the bedroom should be particularly low. Warm white light around 3,000 K creates a calm mood in the bedroom, promotes relaxation and prepares you for the night. Neutral white light is more stimulating in the bedroom and belongs at most by the wardrobe. Daylight white does not belong in the bedroom in the evening because it keeps you awake and can disturb sleep. Two reading lamps with warm light by the bed will not disturb your partner, and a dimmable night light is enough for orientation at night. More on this under Bedroom.
Kitchen: Which colour temperature is suitable for cooking?
In the kitchen you chop, cook and bake, so clear illumination is what counts. Neutral white light shows colours and details reliably and is suitable as general lighting in the kitchen. Even lighting avoids shadows when chopping, and good colour rendering makes food look natural. The colour temperature in the kitchen has to suit the task. The work zone above the worktop can be slightly cooler so that you can see ingredients clearly. Above the dining table or in the kitchen seating area, warm light creates a cosy feel, for example with a pendant light. Daylight white light is usually too cool as general lighting in the kitchen and feels sober. Here too, the light temperature shapes the atmosphere: it decides whether the kitchen feels sober or inviting. If you use the kitchen to relax in the evening, dim the lighting. Further ideas can be found under Kitchen.
Bathroom: Which light colour is suitable for the mirror?
At the bathroom mirror you need clear light for shaving, make-up and personal care. Neutral white light renders skin tones well, provided the light source has a high colour rendering index. When applying make-up, good colour rendering matters at least as much as the number on the packaging. The lighting should be even and avoid shadows on the face, which is why one light source on each side of the mirror is worthwhile. For the bathtub, warm light that invites you to relax is suitable. You will find suitable models under Bathroom.
Study and office: Which light colour aids concentration?
For the colour temperature at the desk, neutral white to daylight white light is common. It feels alert and is considered to aid concentration. Many people find cool light colours pleasant for concentration when working at a screen. If you find daylight white too cool in the study, choose neutral white light; it is less harsh. Warm light is perceived as less stimulating at the workplace. More important than the Kelvin value is sufficient light output; work surfaces should be free of shadows and glare. How strongly people react varies from person to person, so try out different values. You will find more models under Office.
How does light colour affect sleep and biorhythm?
Light controls the sleep-wake cycle, and colour temperature plays a part in this. In the evening, bright light with a high proportion of blue delays the rise of the hormone melatonin, while with dim, warm light melatonin production starts earlier. Blue light has a shorter wavelength than red light. How strongly light colour itself has an effect has not yet been clearly established by research: some studies consider brightness to have a stronger influence than the Kelvin value. A low light temperature in the evening supports the biorhythm, promotes well-being and creates a relaxing atmosphere in the living room. As a guideline for everyday life: during the day, light can be bright and neutral to cool; in the evening, dimmed, warm light and lower brightness are the better choice.
How do I adapt colour temperature to the time of day?
The colour temperature does not have to stay the same all day. In the morning, neutral white light in the kitchen and bathroom helps you wake up. During the day, the lighting at the desk can be daylight white and support concentration. In the evening, switch to warm white light in the living room to relax, and dim the light sources in the bedroom before going to bed. With adjustable light colour, this change is possible with a single light source. Without this function, combine several light sources and switch them according to the time of day.
How do I go about lighting planning?
Start with how the room is used: what happens in the room, and at what time of day? Then define the general lighting and choose its light colour. Next, add separate lighting to individual zones such as the reading spot, dining table or mirror. Keep the colour temperature within a room as similar as possible so that the light feels calm. Finally, check the information on light output, as it determines whether the room is lit brightly enough. Planning a room works best if you think about function and effect first and only then about the individual model.
What is the difference between 2,700 K and 3,000 K?
Both values are considered warm white. A lamp with 2,700 K appears yellowish white and is reminiscent of an incandescent bulb; at 3,000 K the colour appears slightly clearer. The range around 3,000 K is the guideline for living spaces. In the living room and kitchen, the difference is usually only noticeable in direct comparison.
How can I tell the colour temperature of a lamp?
The colour temperature is stated in Kelvin on the packaging and in the technical data of the light, often with an addition such as warm white or daylight white. It can be measured with a colour meter. For home use, checking the stated value is sufficient.
Can I set or change the colour temperature?
Yes, but not with every light. There are four ways.
- Change the bulb: A different bulb changes the light colour. Pay attention to the socket and the Kelvin value.
- Lights with CCT function: CCT stands for Correlated Colour Temperature. Depending on the model, you set the light colour in steps using a switch or remote control, for example from warm white to daylight white.
- Dim to warm: When dimmed, the light colour automatically becomes warmer, as with an incandescent bulb.
- RGB lights: They mix red, green and blue and also produce colours beyond white. White tones are created when the colour components are mixed accordingly.
Important: ordinary dimming does not change the colour temperature. An LED with 3,000 K stays at 3,000 K when dimmed; only the brightness decreases.
The GLOBO Lighting range includes lights with adjustable light colour. Among the ceiling lights, there are also models with RGB colour change. Depending on the model, a dimmer, a remote control or a night light function is included. The Kelvin range varies from model to model. For models with several settings, the technical data lists every Kelvin value; for a fixed white tone, exactly one Kelvin value. Use the filter in the Ceiling lights, Pendant lights and Chandeliers categories to display GLOBO models that offer light colour, dimmer and remote control.
What should I look for when buying a lamp with adjustable light colour?
First check the colour temperature range in the technical data. For models with a CCT function, several Kelvin values for the individual settings are usually listed there. The wider the range, the more scope you have with the light colour. With an RGB function, it is worth checking how the white tones are set. Also check whether a dimmer, remote control or memory function is included so that your setting is retained.
What is the difference between colour temperature and colour rendering?
Colour temperature tells you what colour the light is. The colour rendering index (CRI, Ra) describes how natural colours appear under a light source. It compares the light source with a reference light source such as sunlight. The maximum value is 100; a value of 80 or more is considered good colour rendering. Two bulbs with the same Kelvin value can render colours differently well. When applying make-up, choosing clothes or looking at art, it is worth checking the CRI value.
Can I mix different light colours in one room?
Yes, if the colour temperatures go together. If you mix lamps with very different Kelvin values in one zone, the light looks restless. A proven approach is to choose a uniform base tone for the lighting and set accents and work areas apart in a targeted way. In the living room, this means: ceiling light and floor lamp in warm white, the reading lamp slightly more neutral.
In brief: Which light colour suits when?
Warm white stands for relaxation, daylight white for concentration, and neutral white sits in between as an everyday solution. Good lighting consists of several light sources. Decide according to how the room is used, set the colour temperature if possible and dim the light in the evening. At GLOBO Lighting you will find lights for each room; the details on Kelvin, lumen and dimmability are listed with each model.