Casper Glow Light Review
A bedside light designed around how light affects sleep. The thinking behind it is worth more than the product.
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Verdict
A bedside light that dims warm as it fades, designed around how light affects sleep. Casper left the UK in July 2020 so there is no score here, and the thinking behind the product is worth more than the product, because evening light is one of the few sleep variables you can change tonight for almost nothing.
Who should buy it
Nobody in the UK, since there is no UK channel. Read the section below and change your bulbs instead.
Who should avoid it
Anyone relying on a gadget when a two pound bulb and a habit do the same job.
See the current Casper offer
Casper withdrew from the UK in July 2020. There is no UK direct channel.
No code needed. The discount is applied automatically at checkout. Opening the site in a new tab.
Casper on Amazon UK
Marketplace listings only, with no UK trial and no UK warranty route.
No code needed. Prices on Amazon change frequently, so check the seller and the returns terms before you buy. Opening in a new tab.
| Specification | Detail |
|---|---|
| Type | Dimming bedside light |
| Design idea | Warm, dimming light in the evening rather than bright white |
| UK availability | None. Casper withdrew from the UK in July 2020. |
| Score | Withheld. There is no UK product. |
| What matters more | The colour temperature and brightness of the light you already own |
How evening light actually affects sleep
This is the useful part of the page and it applies whatever light you own.
Your body clock is set largely by light. Light exposure in the evening suppresses melatonin release and pushes your internal clock later, which makes falling asleep harder and shifts the whole night.
Blue wavelengths do this most strongly, which is why blue light gets the attention. But intensity matters as much as colour: a very bright warm light will suppress melatonin more than a dim cool one. Both variables count.
So the two things to change in the last hour or two before bed are the colour temperature and the brightness of whatever is lighting the room. Warm and dim beats cool and bright, and the difference is larger than most people expect.
The corollary is worth knowing too: bright light in the morning helps set the clock the other way. Getting outside within an hour of waking does more for sleep than most things you can buy, and it costs nothing.
What to do instead, for almost nothing
The two pound version
Change the bulb. Bulbs are sold by colour temperature in kelvin. Look for 2,700K or lower for a bedside lamp. Anything at 4,000K or above is daylight white and belongs in a kitchen, not a bedroom.
Use a lamp, not the ceiling light. Lower and dimmer is better than overhead and bright, and a lamp shaded so the bulb is not in your eye line matters more than the bulb itself.
Turn on night mode on your phone and laptop. Built in, free, and it shifts colour temperature automatically.
Dim everything an hour before bed. The habit does more than any single device.
None of that requires a smart light, and a smart light without the habit will not help. If you want one anyway, buy a dimmable warm bulb from any brand that sells in Britain.
Why there is no score
Casper is not sold in the UK
Casper ceased UK and European operations in July 2020. There has been no UK direct channel since, and no UK entity handling returns or warranty claims.
It is still recommended in current UK best-of lists, which is what happens when a page that ranks is left unchecked for years. See the Casper review for the full account and a four-question test for any mattress review.
A correction worth making
Commonly repeated, and wrong
Blue light gets almost all the attention in evening sleep advice, and intensity matters as much as wavelength. A very bright warm light will suppress melatonin more than a dim cool one, so dimming the room matters alongside shifting the colour. The advice that actually works is warm and dim in the last hour or two before bed, and bright light within an hour of waking, which sets the clock the other way and costs nothing.
Should you buy it?
There is nothing to buy here in Britain. Change the bulb instead: 2,700K or lower for a bedside lamp, use a lamp rather than the ceiling light, and dim everything an hour before bed.
Then get outside within an hour of waking. Those two habits do more for sleep than any device sold for the purpose.
Questions people ask
Does blue light really affect sleep?
Light exposure in the evening suppresses melatonin and pushes your body clock later. Blue wavelengths do this most strongly, but intensity matters as much as colour: a very bright warm light suppresses melatonin more than a dim cool one.
What is the best light for a bedroom?
A bulb at 2,700K or lower, in a lamp rather than the ceiling light, dimmed in the last hour or two before bed. Anything at 4,000K or above is daylight white and belongs in a kitchen.
What helps sleep more than anything you can buy?
Bright light within an hour of waking, which sets your body clock the other way, and dimming everything an hour before bed. Both are free and both do more than any device sold for the purpose.