If you have just unboxed an LED mask, the colour buttons are the first confusing thing. Seven modes, no explanation, and most product listings only say "choose your colour." Here is what each wavelength is actually used for, and how to pick one.
Why wavelength matters more than colour
Colour is what you see. Wavelength, measured in nanometres, is what the device actually emits, and it decides how far the light travels into skin. Shorter wavelengths like blue stay near the surface. Longer ones like red and near-infrared reach deeper. That is why a blue mode and a red mode are used for completely different concerns even though they sit on the same device.
If a mask does not publish its wavelengths, you cannot compare it to anything. Two masks can both say "red light" and emit different things. Ours runs from 440 nm to 630 nm across seven colours, plus 850 nm near-infrared — those are the numbers to hold any seller to.
Blue, around 440–470 nm
The shortest wavelength on the device, staying closest to the surface. Used for skin that is prone to breakouts and congestion. It is the mode most people reach for during a bad week rather than every day.
Green, around 520 nm
Used when tone looks uneven or areas of the face look flushed. The goal is a calmer, more even appearance rather than a change to the skin itself.
Yellow, around 590 nm
Used for dull, tired-looking skin. A common choice after travel, poor sleep, or through winter.
Red, around 630 nm
The most widely studied wavelength of the visible range, generally used for the appearance of fine lines and skin firmness. If you only ever use one mode, most people use this one.
Near-infrared, 850 nm
Invisible to the eye and the longest wavelength on the device, so it travels furthest. Used alongside red for the look of ageing skin. If your mask runs it at the same time as red, you will only see the red.
How to choose, practically
Pick the mode that matches your main concern and stay with it for several weeks before judging. Switching colours every session makes it impossible to tell what, if anything, is doing something. Consistency matters more than session length: ten minutes several times a week beats an hour once a fortnight.
What to check before buying any mask
- Published wavelengths. If the listing only says "7 colours," there is nothing to compare.
- Coverage and fit. A flexible silicone shell follows the face, so the light sits at an even distance instead of hovering over the cheekbones.
- Weight. Ours is 1.47 lb. Anything much heavier is a mask you will stop wearing.
- Cordless or not. A cable decides whether you sit still for ten minutes or carry on with your evening.
- Contraindications listed. A seller who hides these is not one to trust.
Who should not use one
LED masks are generally not recommended for pregnant women, children, anyone with photosensitivity, or anyone with a thyroid condition. If you are treating a diagnosed skin condition, speak to a dermatologist first.
LED masks are cosmetic devices, not medical treatments, and are not intended to diagnose or treat any condition. Any change is to the appearance of skin, and results differ from person to person.