Colour temperature: why 2200K and 5000K are not the same night

Every lamp on our shelf has a colour temperature in kelvin printed on the listing, and it is the most useful number on there. It describes whether the light looks like a candle or like noon, and at two in the morning that difference is the whole point.

What kelvin actually describes

Confusingly, a lower kelvin number means a warmer, more orange light and a higher number means a cooler, bluer one. A candle sits around 1900K, a traditional filament bulb around 2700K, an overcast daylight sky around 6500K.

The scale describes the colour of the light itself, not its brightness. A very dim cool-white light is still cool white.

Why warm light suits the night

Light with a strong blue component is the signal the body uses to decide it is daytime. Cool-white light late at night therefore works directly against getting back to sleep, for the adult as much as for the baby.

Warm light at 2200 to 2700K carries far less of that signal, which is why every product designed for night feeds is at the warm end.

The practical ranges

For a night light or a feeding lamp, look for 2200K to 2700K. For a bedside lamp used for reading in the evening, 2700K to 3000K is comfortable. Anything at 4000K or above belongs to a kitchen or a workspace, not to a nursery at night.

Some lamps offer a colour cycle; if so, check that it includes a genuinely warm setting rather than only bright colours.

Dimming matters as much

A warm light at full brightness still lights the room. Stepless dimming, or at least three or four levels, lets you use the minimum you actually need. The lowest useful setting is usually far dimmer than people expect.

Lamps that remember the last brightness after being switched off are worth seeking out — you set it once and never fumble again.

Where to put it

Out of reach of the cot, and pointing away from the baby’s face. A light bouncing off a wall or a ceiling gives usable illumination with much less glare than one shining directly.

If it is portable, decide where it lives when not in use so you can find it in the dark.

Rechargeable or plugged in

A rechargeable lamp can be carried to wherever you are feeding, which is usually more useful than a fixed one. Check the run time at the brightness you will use, not the headline figure, which is typically quoted at the lowest setting.

Plug-in sensor lights are excellent for a hallway or a landing, where you want light only when someone passes.

Screens count too

A phone at full brightness undoes a carefully chosen warm lamp instantly. Turning on a phone’s warm display mode and dropping the brightness before a night feed is free and makes as much difference as the lamp does.

It is worth mentioning because it is the most common thing that spoils an otherwise well-lit night routine.

Reading a listing

Colour temperature in kelvin, dimming type, run time on a charge, and whether it remembers its setting. All four are on every lamp on the shop page, because between them they decide whether a light suits a nursery. The counter on Canal Street can show you two side by side if you want to see the difference.

Brightness and colour are separate settings

People often reach for a dimmer when the real problem is colour, or change the bulb when the real problem is brightness. They are independent: a very dim 5000K light is still daylight-coloured, and a bright 2200K light is still too much light at three in the morning.

Fix the colour first, because it is a fixed property of the lamp or bulb, and then use dimming to set the level. A lamp that gets both right is one you will keep for years; one that only gets brightness right will be replaced.

Getting the same light in every room you use at night

The route from bed to nursery to bathroom usually passes three light sources of three different colours, and the coolest one undoes the others. Matching them is cheap: a warm bulb in the landing fitting and a warm sensor light in the bathroom cost very little and make the whole route consistent.

Buy them at the same time and to the same specification. Mixed colour temperatures along a route are more disruptive than any single lamp being slightly too bright.

The short version

• Warm light below about 2700K is what you want at night.
• Cool white above 4000K is daylight-shaped and suppresses sleepiness.
• Dimmable matters as much as colour temperature.
• Amber and red-shifted light is the least disruptive of all.

From our shelves

• NICKLUC Egg Night Light for Nursery: Rechargeable Baby Touch Lamp — $21.59
• Egg Light for Nursery, Baby Night Light for Feedings & Diaper Changes — $18.99
• Duck Night Light LED, Lying Flat Silicone Duck Lamp, 3-Level Dimmable Cute Night Light — $16.99

Where to go next

Browse the full range on the shop page, read the frequently asked questions before ordering, or check delivery timing on the Shipping Policy page. If you would rather ask a person, contact us — the phone reaches the counter.