Monitor height and distance

The head weighs a lot and sits on top of a flexible column. Tilt it forward and the muscles at the back of the neck hold it there, continuously, for as long as the screen is where it is.

You don’t decide to do this. The screen decides. Put text somewhere and your eyes go to it, and your head follows your eyes. So a monitor isn’t positioned for comfort — it’s positioned to determine where your head spends the day, which is why it’s worth more attention than it usually gets.

Set the chair first. Screen height depends on where your eyes end up, and your eyes depend on the chair.

Height: the top of the screen, not the middle

The convention people half-remember is “the top of the screen at eye level.” It’s a decent starting point and it’s worth knowing why, because the why tells you when to deviate.

Your eyes have a comfortable range that extends further downward than upward. Looking slightly down is easy and sustainable; looking up is not, and it also opens the eyes wider, which dries them out. So you want the whole screen at or below eye height, with the top edge roughly where your eyes are when you’re looking straight ahead.

MONITOR HEIGHT — the check
  Sit as you normally work. Close your eyes.
  Let your head settle into a comfortable, neutral position.
  Open your eyes.

  · Looking at the top third of the screen        → height is right
  · Looking above the screen, at the wall/bezel   → screen is too low
  · Looking at the desk below the screen          → screen is too high

The closed-eyes part matters. Ask yourself where you’re looking with your eyes already open and you’ll answer from where the screen is, which is circular. Let the head settle first, then look.

Deviations that are legitimate:

Bifocals or progressive lenses. These require you to look through a specific part of the lens, which usually means tilting the head back for a screen at standard height. Lower the screen until your head is neutral and you’re reading through the right zone. This will look far too low to anyone else and is correct for you.

Very large screens. With a big display the “top at eye level” rule puts the bottom uncomfortably low. Lower the whole thing so the vertical middle sits below eye height and accept looking up slightly at the top edge — you don’t work at the top edge.

How to raise it, for free

Monitor stands are the archetypal thing you don’t need to buy.

Books. Wide ones. Hardbacks. Stack them so the base plate is fully supported. A ream of paper is almost exactly the height most monitors need to come up. A sturdy box with something dense inside.

The requirements are: stable, level, wide enough that the monitor’s foot isn’t overhanging, and no higher than needed. Test it by nudging the desk — if the screen wobbles noticeably, add width.

A monitor arm is the upgrade, and its real advantage isn’t the height, it’s that changing the height becomes free. If you share a desk, or you alternate sitting and standing, that matters. Otherwise books work.

Lowering a monitor is harder than raising it, because most stands have a minimum. If your screen is too high at its lowest setting, the fix is usually to raise your chair and rebuild the footrest — which is why the chair comes first in the chain, and why doing this out of order means doing it twice.

Distance: far enough that you stop leaning

The common instruction is “about an arm’s length.” Fine as a first guess, and it’s the wrong kind of rule, because it depends on the size of the screen, the size of the text, and your eyes.

The functional definition: far enough that you can read comfortably without leaning in, and see the whole screen without moving your head. Those two pull in opposite directions, and where they meet is your distance.

MONITOR DISTANCE — the check
  Work normally for a few minutes. Then notice:

  · You're leaning toward the screen           → too far, or text too small
  · You're moving your head to see the edges   → too close, or screen too large
  · You're squinting                            → text too small (fix the text first)
  · Neither                                     → distance is right

The leaning-in one is the important observation, because leaning forward unsupported is the posture that costs the most and it happens gradually enough that you don’t catch yourself.

And note the order in the second and third rows: if you’re leaning in to read, increase the text size before you move the monitor closer. Everyone knows this and almost nobody does it, out of some vague sense that larger text is an admission of something. Increase the size. Then set the distance for the whole screen.

Tilt, angle, and the second monitor

Tilt. The screen face should be roughly perpendicular to your line of sight, which for a screen below eye height means tilted back slightly at the top. A screen tilted the other way reflects the ceiling light straight into your eyes.

Two monitors — the arrangement depends on how you use them. If you genuinely use both equally, put them symmetrically with the join in front of you so you turn equally each way. If one is primary and the other is for reference, put the primary directly in front and the secondary to the side. The common mistake is the split-the-difference setup: primary slightly off-centre, so you spend all day with your head rotated a few degrees in one direction, which is a small constant demand rather than an occasional large one.

Laptop plus external monitor is a special case with its own failure, covered in the laptop post.

Glare, which people fix by moving their head

Worth including here because glare is a screen position problem that presents as a neck problem. When there’s a reflection on the screen, you don’t consciously move — you shift your head slightly until the reflection isn’t over the text, and then hold there.

Sources, in order of how often they’re the cause:

A window behind you. The most common. It puts a bright rectangle in the middle of your screen. Turn the desk 90 degrees so the window is to one side, or close the blind.

A ceiling light above and behind. Second most common, and harder to notice because it’s dim enough to be invisible until you look for it. Check by turning the screen off and looking at the black glass: whatever you can see is what’s competing with your work.

A window in front of you. Doesn’t reflect, but puts a bright field behind a darker screen, which makes you squint. Less bad than behind, still worth avoiding.

The black-screen check takes five seconds and finds nearly all of it.

When your head still isn’t neutral

If the screen is right and you’re still craning, look for something else pulling you forward: a document flat on the desk that you keep reading, a phone you’re glancing at, or a keyboard so far away you’ve moved your whole torso toward it. A document holder — or a second stack of books — brings paperwork up next to the screen instead of down on the desk.

And the standing reminder: persistent neck pain, or numbness or tingling into an arm, is a reason to see a clinician, not a reason to keep adjusting your stand.