Engadget
It’s not just about distance; height and tilt matter too.
Whether you work from home or are at the office full-time, you should have a proper computer setup: organized desk, comfortable office chair, proper lighting, and useful accessories. Once you have the gear, you need to position everything for the best ergonomic experience. This includes having your display eye-level at the proper distance away from your face. But what is that distance?
The answer depends on the size of your monitor, but the simplest guidance to follow is the arm's length rule. To meet this, stretch out your arm and position the monitor that length away from your body, such that your fingers are able to touch the screen. The proper view also requires having the right height and tilt, which we'll discuss (along with more specific rules for smaller- or larger-than-average monitors).
The reason to keep the monitor at a good distance is to prevent eye strain and fatigue. You don't want it to be so far away that you squint or strain to see properly. On the other end, you should also avoid leaning forward, which can aggravate your neck and back and lead to poor posture habits.
The arm's length rule is a good starting point because the ideal distance between your eyes and your monitor is anywhere from 20-28 inches. That upper limit roughly lines up with the average adult arm length, which is about 28-31 inches. The Occupational Safety and Health Administration (OSHA) recommends that you keep the monitor about 20-28 inches away from you, for 24-inch displays. For 27-inch monitors, consider increasing that distance to 24-32 inches.
Once you reach monitor sizes of 32 inches or larger, you'll need to be even further away to keep the display within your field of view so you don't need to move your neck around all the time. This is also where monitor resolutions have a great impact. Higher resolutions let you sit closer to the screen without being able to see individual pixels, which is why many 32-inch monitors are at least 1440p. When you get up to this size, a comfortable spot should be anywhere from 34 to 38 inches away.
Since laptops have much smaller screens, it's recommended to invest in a separate keyboard and mouse so you can maintain the proper arm's length distance while still being able to work. In any of these cases, your eyesight may require you to increase the font size or screen scaling.
Once you have the right distance, there are a few other elements to consider. The monitor should be positioned front and center, so you're facing forward while viewing it. It also needs to be at eye level, with laptop viewing angles commonly being too low for many people. Position the top of the monitor either at or below your eye level, with the middle of the screen 15-20 degrees below your eye level. You can adjust your chair or desk (if either is height-adjustable) to accommodate this, or use an accessory like a laptop riser. As you adjust the chair to accommodate the right height, make sure your feet can still sit flat on the floor.
If you wear bifocals, which require you to look through the bottom portion of your glasses to see close-up, you'll want to lower the monitor a little more to compensate. Also, you should tilt the screen back anywhere from 10-20 degrees, or up to 30-45 degrees if you wear bifocals. Don't forget to adjust the screen's brightness so it's not overly intense on your eyes, or use an anti-glare screen filter if the monitor doesn't already have this technology built in.
It's worth noting that these rules also apply if you have a multi-monitor setup. Tons of great monitors are available if you're looking to add another display.