Lens guide
Amber vs red vs clear lenses: which colour is best for sleep?
For the 1–2 hours before bed, amber is the practical choice for most people. A deep-amber lens can filter the blue-green light the body clock is most sensitive to while screens and text stay usable. Dark-red lenses change colours more, and clear blue-light glasses are made for daytime screen comfort.
How do amber, red and clear lenses compare?
Figures vary between brands, so check each product’s stated blocking percentage and wavelength range.
| Compared on | Amber | Dark red | Clear |
|---|---|---|---|
| Made for | The 1–2 hours before bed | Evening and night-time use | Daytime screen comfort |
| What it filters | Blue and blue-green light. SleepSpec blocks 98% across 400–520 nm | Blue and green light; the range varies by brand | A fraction of blue light on most pairs |
| How the view looks | Strongly amber; screens and text stay usable | Red; less natural colour than amber | Close to normal |
| Sold by SleepSpec | Yes, one pair at £29.99 | No | No |
Which colour blue-light glasses are best for sleep?
Pick the lens by what it blocks, not by its name. The body clock is especially sensitive to short-wavelength light around 480–490 nm, so look for a stated blocking percentage across a range that covers that band.
SleepSpec’s deep-amber sleep glasses block 98% of blue-green light across 400–520 nm. Wear them for 1–2 hours before bed and take them off at lights-out. See amber glasses for sleep for what to look for in a pair.
Do clear blue-light glasses work for sleep?
Clear blue-light glasses are made for daytime screen comfort, not for the hours before bed. Most pairs filter only a fraction of blue light, which is why they look clear: a lens that removed most blue-green light would look amber.
If a clear pair is sold for sleep, check its stated blocking percentage and wavelength range. A clear lens is the right choice if you want normal colours during the day.
Amber vs red lenses: what is the difference?
Both are tinted for evening use. Dark-red lenses filter further into the green part of the spectrum, so they change colours more. SleepSpec’s deep-amber lens preserves more natural colour than dark-red lenses.
Amber is still a strong change, and colours look different. Your eyes adjust within a few minutes, much as they do with tinted sunglasses, and the view starts to feel normal. If you want the widest filtering and accept the colour change, a dark-red lens is the alternative to consider.
Who should not buy amber sleep glasses?
SleepSpec is one non-prescription pair of deep-amber glasses. Choose something else in these cases.
- You need prescription lenses. SleepSpec usually fits over prescription frames, but it is not a dedicated fit-over model and the fit is not guaranteed.
- You want a clear lens for daytime. Deep-amber lenses are not intended for all-day wear.
- Your evening needs accurate colour. Take the glasses off for colour-critical tasks, and do not wear them while driving.
Is the research on blue-light glasses settled?
No. In a randomised crossover trial of 14 adults with insomnia symptoms, amber lenses were linked to approximately 29 minutes more actigraphy-estimated sleep and improved insomnia scores compared with clear lenses. A 2021 review found evidence for quicker sleep onset in selected groups, although later reviewers found the overall sleep evidence mixed.
These studies did not test SleepSpec, and individual results vary. See the research page, the FAQ and the UK buying guide.