Eye Strain: Settings That Help
Long hours at a screen leave many people with tired, dry or blurry eyes. This guide makes no medical claims; it collects what the eye-care bodies recommend about setting up the screen.
The eye-care bodies' advice comes down to a few settings and habits: match the screen's brightness to the room, cut glare, sit about an arm's length away with the screen slightly below eye level, enlarge text instead of leaning in, blink, and follow the 20-20-20 rule: every 20 minutes, look at something 20 feet away for 20 seconds. If symptoms persist, the advice is to see an eye doctor.
Hours at a screen leave many people with eyes that feel tired, dry or unfocused by the end of the day. The American Optometric Association calls it computer vision syndrome, or digital eye strain: “a group of eye- and vision-related problems that result from prolonged computer, tablet, e-reader and cell phone use.” It lists the common symptoms as “Eyestrain. Headaches. Blurred vision. Dry eyes. Neck and shoulder pain.”
This guide makes no medical claims. It collects what the eye-care bodies recommend about the one part of the problem you can change from your chair: how the screen is set up and used.
Brightness: match the room
The most common piece of advice is also the simplest. The American Optometric Association’s screen-time guidance says: “Room lighting should be about the same as the brightness of the screen of an electronic device, not significantly brighter or dimmer.” The American Academy of Ophthalmology makes the same point from the other side: a screen that glows brighter than its surroundings makes the eyes work harder, so it suggests adjusting the screen to the light around you.
- 1
In daylight, the screen usually needs to be brighter; in the evening, lower.
- 2
In a dark room, either turn a lamp on or bring the screen well down. The Academy notes that working at a computer in the dark will not damage your eyes, though it may tire them.
- 3
Use automatic brightness if your device has it, which follows the room for you.
If your screen seems to flicker at low brightness, the Screen Flicker and PWM guide explains why some screens do.
Glare: move the light, not your head
Reflections make you squint and lean. The Association’s advice is to “position the computer screen to avoid glare, particularly from overhead lighting or windows”, and to “use blinds or drapes on windows and replace the light bulbs in desk lamps with bulbs of lower wattage.” Where that is not possible: “consider using a screen glare filter.” The Academy also mentions matte screen filters.
Distance and position
The Association gives its optimal setup precisely:
"Optimally, the computer screen should be 15 to 20 degrees below eye level (about 4 or 5 inches) as measured from the center of the screen and 20 to 28 inches from the eyes." — American Optometric Association
The Academy’s figure is similar: about 25 inches, roughly an arm’s length, with the screen placed so you look slightly down at it. For smaller devices, the Association’s screen-time guidance suggests “at least 13 to 20 inches for smartphone, small tablet or laptop” and “greater than 20 inches for full-size laptop or computer monitor.”
Text size: zoom in, do not lean in
When text is too small, the instinct is to move closer. The Association advises the opposite: “Use the zoom feature to see small print and details, rather than bringing the device closer to your eyes, which taxes the visual system.”
On a computer, there are two places to do that: the browser’s own zoom, which works on any page, and the operating system’s scale setting, which enlarges everything. The Resolution, PPI and Aspect Ratio guide explains how scaling works, and why lowering the screen’s resolution is the wrong way to make text bigger.
Breaks: the 20-20-20 rule
Both bodies recommend the same habit. In the Association’s words: “take a 20-second break to view something 20 feet away every 20 minutes.” It also suggests “resting the eyes for 15 minutes after two hours of continuous computer use.”
Remembering is the hard part. A Countdown Timer set to 20 minutes, or the work-and-break rhythm of the Pomodoro Timer, is one way to be reminded.
Blink
Concentrating on a screen changes how often you blink. The Academy reports that people normally blink about 15 times a minute but only about 5 to 7 times a minute at a screen, and suggests artificial tears when the eyes feel dry. The Association’s advice is simply: “try to blink frequently.”
On blue light, the eye-care bodies disagree. The American Academy of Ophthalmology says there is no scientific evidence that blue light from devices damages the eye, and does not recommend blue-light-blocking glasses for computer use. The American Optometric Association says blue light from screens "can negatively affect vision over the long term." This guide takes no side.
Evenings: night mode and dark mode
The Academy describes night mode as a setting that lowers screen brightness and reduces the contrast between a bright screen and a dark room, and suggests switching devices to it in the evening. It also notes that less bright screen light late at night can make it easier to fall asleep.
ScreenTail’s own pages follow your device’s light or dark setting. Its Warm White and Amber screens are something different: full-screen colors to use as a light for photos and video calls. No claim is made that they help with eye strain, and none of the sources quoted here recommends a screen color for it.
When settings are not enough
Setting up the screen well is worth doing, but it is not a diagnosis. The Association says digital eye strain “can be diagnosed through a comprehensive eye examination”, and advises that anyone “spending several hours staring at digital screens and/or experiencing any symptoms” should talk to an optometrist about it. The Academy advises seeing an ophthalmologist if your eyes are consistently red, blurry or watery, or become painful or sensitive to light.
Questions
Do blue-light glasses help?
The eye-care bodies disagree. The American Academy of Ophthalmology says there is no scientific evidence that blue light from digital devices damages the eye, and it does not recommend blue-light-blocking glasses for computer use. The American Optometric Association says blue light from screens "can negatively affect vision over the long term" and that special lens tints and coatings can reduce it. This guide takes no side; an eye doctor can advise on your own eyes.
Does night mode or dark mode help?
The American Academy of Ophthalmology describes night mode as lowering screen brightness and reducing the stark contrast between a bright screen and a dark room, and suggests using it in the evening. It also notes that less screen light late at night can make it easier to get to sleep.
Is working in a dark room bad for my eyes?
The American Academy of Ophthalmology says working at a computer in the dark will not damage the eyes, though it may tire them. The American Optometric Association's advice is to keep room lighting "about the same as the brightness of the screen".
Will ScreenTail's warm screens help with eye strain?
No such claim is made. The Warm White and Amber screens are light sources for photos, video calls and ambience. None of the sources quoted here recommends a screen color for eye strain.
When should I see an eye doctor?
The American Optometric Association says digital eye strain "can be diagnosed through a comprehensive eye examination" and advises talking to an optometrist if you spend several hours a day at screens or have symptoms. The American Academy of Ophthalmology advises seeing an ophthalmologist if your eyes are consistently red, blurry or watery, or become painful or sensitive to light.
How this guide was made
The definition, symptoms and setup advice are quoted from the American Optometric Association's pages and its screen-time guidance, with the dates they were read. The American Academy of Ophthalmology's positions are summarized in this guide's own words, with links, because its website does not permit its content to be reproduced. Where the two bodies disagree, both views are given. The guide makes no medical claim of its own.
No diagnosis, treatment or product recommendation, and no claim that any ScreenTail tool relieves eye strain. Figures for distance and position are the ones the sources give; where one body gives several ranges, the one it calls optimal is quoted. Eye conditions that need an eye doctor are outside this guide.
- 01The definition and symptoms of computer vision syndrome, the 20-20-20 rule, screen distance and angle, glare, blinking, blue light, and diagnosis by eye examination: American Optometric Association, Computer vision syndrome — retrieved Sep 25, 2026.
- 02Room lighting matching screen brightness, zooming rather than moving closer, viewing distances by device, and when to talk to an optometrist: American Optometric Association, Eye Health Guidance for Screen Time (PDF) — retrieved Sep 25, 2026.
- 03Screen brightness relative to the room, matte filters, sitting about 25 inches away, blink rates, artificial tears, and when to see an ophthalmologist (summarized; published June 27, 2024): American Academy of Ophthalmology, Computers, Digital Devices, and Eye Strain — retrieved Sep 25, 2026.
- 04Its position on blue light from digital devices and on blue-light-blocking glasses (summarized; published March 10, 2021): American Academy of Ophthalmology, Should You Be Worried About Blue Light? — retrieved Sep 25, 2026.
- 05Night mode and dark mode, brightness and contrast with a dark room, and sleep (summarized; published May 7, 2019): American Academy of Ophthalmology, Should You Use Night Mode to Reduce Blue Light? — retrieved Sep 25, 2026.
- 06That working at a computer in the dark does not damage the eyes but may tire them (summarized; answered December 5, 2022): American Academy of Ophthalmology, Is working on a computer in a dark room bad for my eyes? — retrieved Sep 25, 2026.
Try the tools
Vivek Kumar runs ScreenTail from New Delhi. He has worked with computers for about 25 years and studied Computer Science. He is not a display engineer or a color scientist, and each guide says where its facts come from so you can check them.