Short answer: the most effective blue light glasses are the ones matched to when you wear them. For the evening, when cutting blue light matters most, that means an orange or red lens: our red SleepAidMax lens blocks 99.7% of light across 380–580nm, and our orange SleepAid lens 99% across 380–550nm. For daytime screens, a clear or yellow lens filters less but keeps you seeing normally. Whatever you choose, look for a measured blocking figure with its wavelength range, because lenses that look alike can filter very differently.
Below: how the tints compare, what to look for, and which to choose.
Blue Light Basics
Blue light is the part of visible light between roughly 400 and 500nm. The sun is by far the biggest source; screens and LED lighting give off much less. During the day, blue light helps you feel alert. In the evening, bright, blue-rich light can delay the rise of melatonin, the hormone that tells your body it's getting dark.
That's why "effective" depends on the time of day. In the evening, the goal is to cut as much blue light as possible. During the day there's no need to cut it heavily, and the American Academy of Ophthalmology says the light from screens doesn't damage the eyes.
Which Tint Is Most Effective?
The deeper the tint, the more blue light a lens filters. Our lenses, measured by Micro-Light Optics:
| Lens | Blocks | Light transmission | Best for |
|---|---|---|---|
| Clear (InvisiAid) | 35% across 400–500nm | 86% (Category 0) | Daytime screens, color-accurate work |
| Yellow (ScreenAid) | 60% across 400–500nm | 79% (Category 1) | Daytime screens, a warmer look |
| Orange (SleepAid) | 99% across 380–550nm | 48% (Category 1) | The two to three hours before bed |
| Red (SleepAidMax) | 99.7% across 380–580nm | 22% (Category 2) | The last hour before sleep |
Orange and red lenses change colors strongly and are not for driving. There's more on each in our guides to orange lenses and yellow lenses.
What About Daytime Screens?
Clear and yellow lenses filter less, and that's fine for the daytime. Just keep expectations realistic: a 2023 Cochrane review found blue light filtering glasses probably make no difference to eye strain in the short term. Tired eyes at a screen usually come from focusing up close, blinking less and glare, so breaks and a good screen setup matter more. Many people still prefer the look of a screen through a clear or yellow lens.
What to Look For
A Measured Blocking Figure
Look for a percentage with the wavelength range it covers, such as "blocks 99% across 380–550nm". "Blocks blue light" on its own tells you nothing. A 2020 study in Clinical and Experimental Optometry measured a range of blue light filtering lenses and found that blocking in the lenses it tested ranged from about 6% to 43%, so the label matters.
Who Measured It
An independent lab result is more reliable than a brand's own claim. Ours are measured by Micro-Light Optics against ISO 12312-1 and ANSI Z80.3, and published on our science page.
Light Transmission and Filter Category
These tell you how dark the lens is and where it's suitable: Category 0–1 for indoors, and anything below 75% light transmission is not for driving at twilight or night.
UV400
UV400 means the lens blocks UV up to 400nm. All our lenses are UV400. UV protection doesn't make a lens a pair of sunglasses, though: for bright sun you need a darker lens too. See do blue light glasses block UV rays?
Comfort
If you'll wear them for hours, a lightweight frame that doesn't pinch matters. If you wear prescription glasses, a clip-on or fit-over pair goes over them.
Frequently Asked Questions
Is 20% Blue Light Blocking Enough?
For daytime screens, it depends what you want from them. For the evening, no: to cut blue light before bed you want an orange or red lens that blocks around 99%.
Which Blue Light Glasses Block the Most Blue Light?
Red lenses. Ours, SleepAidMax, blocks 99.7% of light across 380–580nm. That's too dark for daytime or driving, so it's strictly for the evening.
Are Expensive Blue Light Glasses More Effective?
Not necessarily. Price often reflects the frame and brand. The measured blocking figure is what tells you how much a lens filters. See how much are blue light glasses?
How Do I Choose?
- Match the tint to the time: clear or yellow for the day, orange or red for the evening
- Check for a measured blocking figure and who measured it
- Check light transmission, and never drive in orange or red lenses
- Look for UV400
Conclusion
The most effective blue light glasses depend on when you wear them. In the evening, an orange or red lens that blocks around 99% is the one that makes a real difference to how much blue light reaches you before bed. During the day, a clear or yellow lens is enough if you like it. Whatever you buy, check for a measured figure rather than going by color or price.
Use the Lens Finder to match a lens to your day.
