1. Measure First: Reading Your Own Body Before You Buy Anything

The first tool in a workstation build is a tape measure, plus a pen and something to write on. Desks, monitor arms and keyboards are all sold by numbers: how low and how high a desk goes, how much weight an arm holds, how many keys a keyboard has and how it splits apart. Those numbers only answer your question once you have four of your own, so start there.

There are four body measurements, and each one needs the right posture before the number means anything.

Start seated, because that is where most of the work happens. Sit all the way back in the chair so your lower back is supported. Adjust the seat height until your feet rest completely flat on the floor, your thighs are roughly horizontal, and your knees are about level with your hips. Check the front edge of the seat. There should be a gap of two to four finger-widths between that edge and the back of your knee. If the seat is pressing into the back of your knee, slide back or use a shallower position, because that pressure squeezes the blood flow in your leg.

If the chair won't go low enough to get your feet flat, or if you've had to raise it to reach a table that doesn't move, put your feet on something solid before you measure anything: a stack of books, a sturdy box, a proper footrest. Your feet are the base of everything above them. When they hang, your pelvis rolls and your whole upper body settles into a different shape, and the measurement you take from that shape describes a posture you would never choose to work in.

Footwear matters too. For seated measurements, measure in whatever you actually have on your feet at the desk: barefoot if you work barefoot, shoes if you wear them. For standing, always wear the shoes you would really stand and work in. A sole is often half an inch thick or more, and that half inch lifts your elbows and your eyes off the floor by the same amount. Measure in slippers, buy for sneakers, and you've bought the wrong height.

The arm posture is the one people get wrong. Let your upper arms hang straight down at your sides, shoulders relaxed and dropped, not lifted and not pushed forward. Then bend your elbows to somewhere around ninety to a hundred degrees, so your forearms are parallel to the floor or angled very slightly downward. Wrists straight, in line with the forearms, not bent up and not bent down.

Hold that, and measure straight up from the room's floor to the underside of the bony point of your elbow. That is your seated typing height. It is the height the keys under your fingers should sit at, and your mouse too.

Keep the shoulders relaxed because a shrug is worth an inch or two, easily, and it doesn't feel like anything while you're doing it. Lift your shoulders while you measure and you record a number higher than your real one. Then you set your keyboard to that number, and to reach it you shrug all day. It helps to breathe out, let your arms go completely heavy for a moment, and only then bring the forearms up.

Second number, same seated posture. Look straight ahead, level, with your neck at rest and not tilted. Measure from the room's floor up to the center of your pupils. That is your seated eye height. It is a ceiling for the top of your screen, not a target for the middle of it.

Third and fourth numbers, standing. Shoes on. Feet about hip-width apart, knees unlocked rather than jammed straight. Shoulders dropped, upper arms hanging, elbows at that same ninety to a hundred degrees. Measure floor to the underside of the elbow point: that is your standing typing height. Then look level and measure floor to pupils: standing eye height.

A rigid tape measure held against a flat wall is much easier to read than a floppy one held in mid-air, and a second person makes it easier still. Measure each one twice. If the two readings disagree by more than about half an inch, your posture is drifting between attempts, so reset and go again.

The rest of this lesson runs on sample numbers so you can watch the reasoning work; swap in your own as you go. Say you work on a laptop at a kitchen table. You type for long stretches, you're on video calls several times a day, and you do some fiddly image work where a few pixels matter. Nothing about the setup is on purpose. The table was there, the laptop was there, and the arrangement is whatever happened. Say your seated typing height comes out at twenty-six inches and your seated eye height at forty-five. Standing, in the shoes you wear at home, your typing height is forty-one inches and your eye height sixty.

Then measure the room. Write down the height of the current typing surface, from the floor to the top of it. Write down the seat height and whether the feet reach the floor. Write down where the screen sits: how high the top of the picture is off the floor, and how far it is from your eyes when you're working normally. Write down how deep the surface is from front edge to wall, and how wide. Write down where the electrical outlets are and how far away. And get under there with the tape: how much clear space is there between the floor and the underside of the surface, and is anything in the way, such as a drawer, an apron rail, or a table leg where your knees want to be?

Say the kitchen table is thirty inches from the floor to the top, the chair seat is eighteen inches, and your feet do reach the floor. The laptop sits flat on the table, and the top of its screen is about thirty-three inches off the floor. The table is twenty-four inches deep, which is shallow, and the nearest outlet is behind you on the wall.

Compare body to furniture and the problem is right there in the numbers. Your seated typing height is twenty-six inches. The typing surface is thirty. That is four inches too high, so to reach the keys you either lift your shoulders or bend your wrists up, or some of both. Meanwhile your seated eye height is forty-five inches and the top of the screen is at thirty-three, twelve inches lower. So your neck drops forward to read it. Wrists up, neck down, all day.

That four-inch gap involves three different heights that people talk about as if they were one, and the difference matters every time you look at a desk. There is the frame height, which is what the metal legs reach on their own. There is the finished desktop height, which is the frame plus the thickness of the top you put on it. And there is the typing height, which is the finished desktop plus the thickness of your keyboard, measured up to the keys your fingers actually rest on.

Work it forward and it looks like this. Say a frame goes down to twenty-eight inches. Put a one-inch top on it, and the surface is at twenty-nine. Set a keyboard on that whose home row sits an inch above the desk, and the height your fingers work at is thirty. If your seated elbow height is twenty-six, that desk at its very lowest still puts you four inches too high, exactly the gap in the sample numbers. A desk advertised as going down to twenty-eight inches didn't lie to you. It just wasn't describing the number you needed.

Turn the same arithmetic around and you get the rule you'll use when you shop. Take your measured elbow height, subtract the thickness of the top, subtract the height of the keyboard, and what is left is the highest the frame can be. Anything higher and you're back to shrugging, unless something else in the setup moves.

Write all of this down in one place and keep it: a page in a notebook, a note on your phone, a file, anything you can find and add to. Four body numbers, the current surface and seat and screen and space, the outlets, the clearance underneath. Then add one short list at the bottom: what your work actually demands. In the sample setup that is precision work with images, long typing sessions, frequent calls, and a wish to be less stuck in one position. Each demand points somewhere. Precision work argues for a stable screen and a pointing device you can control finely. Long typing argues for getting that typing height right before anything else. Frequent calls will matter later if there is ever a motor or a belt running in the room.

Then make one free change. The biggest measured gap is the four inches between your elbows and the table. The table doesn't move, so you do. Put a firm cushion on the chair, which raises the seat by about two and a half inches and lifts your elbows with it. Your feet no longer reach the floor properly from there, so put a two-inch stack of hardback books under them, flat and solid, and rest your feet on that.

Keep every height measured from the room's floor and watch the arithmetic. The cushion raises your elbows from twenty-six to twenty-eight and a half inches. The table is still thirty inches high, so the gap falls from four inches to one and a half. The books support your feet; they don't change the reference point for measuring the furniture. Your eyes rise with the seat too, from forty-five to forty-seven and a half inches. Remeasure both heights in the supported position rather than relying only on the cushion's stated thickness.

That is a real improvement, not a fix. One and a half inches is still one and a half inches, and your wrists still ride up a little. Free adjustment got most of it and can't get the rest, because the table is a fixed height and the chair only goes so far before your knees start hitting the underside. An adjustment is an adjustment, not a treatment, either. This show can explain mechanics and fit, but no product in it will prevent or cure pain. If something hurts and keeps hurting, that belongs with a qualified person who can assess you, not with a more expensive chair.

Then the screen. Stack books under the laptop and raise it six inches. The top of the picture goes from thirty-three inches to thirty-nine. With the cushion in place, your seated eye height is now forty-seven and a half inches. Using a starting range from eye level to about three inches below it puts the screen-top target around forty-four and a half to forty-seven and a half inches. Thirty-nine is closer than thirty-three, but it's still below that range. You still need to check whether you can read comfortably without bending your neck.

But on a laptop, the screen and the keyboard are one object. Raise the lid six inches and you raise the keys six inches too. That undoes the seat and footrest work and then some: the typing surface goes from one and a half inches too high to seven and a half inches too high. You can't fix both ends of a laptop by lifting it. There is one hinge and two problems.

The only way out is to stop treating them as one object. Lift the laptop and use it purely as a screen, then put a separate keyboard and a separate mouse or trackball down at elbow height. No product is named here. The shape of the problem requires it: two things that need to be at two different heights need to be two things.

So try a smaller lift for now: two inches under the laptop, keeping the cushion and the books under your feet. That puts the screen top at thirty-five inches, but it also raises the typing surface to thirty-two. Against your adjusted elbow height of twenty-eight and a half, the typing gap is now three and a half inches. The smaller stack trades some screen height for a worse keyboard position than the laptop flat on the table. It's a trial to evaluate, not a solved setup.

Then work, because an adjustment you haven't tested is a guess. Write a document for half an hour and take one ordinary video call, and check four specific things. Here is how the sample setup answers them.

Reach: can you get to the keys, the trackpad and your notebook without leaning or stretching? Mostly yes, though the shallow table puts the laptop closer to your face than is comfortable. Visibility: can you read the screen without dropping your chin? Better than before, not solved. Support: are your back and feet actually held? Yes. Foot support is the clearest gain, and the lower back stays against the chair now instead of sliding forward. Unwanted movement: does anything wobble? The cushion slides a little when you shift, and the book stack under the laptop is no place for a heavier screen.

Two more things only show up over a few days. Glare: where the light is, and whether the screen washes out at some hour of the afternoon. And changing position: whether you can shift how you sit now and then instead of being locked into one shape, because holding any single posture for hours is its own problem.

So the record gets updated. Improved: foot support and back support. Not solved: typing height, now about three and a half inches too high with the two-inch laptop stack in place; screen height, with the top at thirty-five inches against an adjusted eye height of forty-seven and a half; and viewing distance on the shallow table. The laptop lift has made the keyboard gap worse than it was immediately after raising the seat. Installed cost so far: nothing. Those measurements and tradeoffs carry forward.

What to write down about your screen

While the tape is out, check whether the stand or riser you already own reaches where your measurements say the screen needs to be. It's five minutes of arithmetic.

Measure the gap from the desktop surface up to the bottom edge of the screen, with the stand at its lowest setting, then again at its highest. Then measure the panel itself, bottom edge to top edge. Add the panel height to each of those two gaps and you have the lowest and highest that the top of the screen can sit above the desk. Add the desk height and you have it as a height off the floor, which is the form your eye-height number is in.

Say you borrow a twenty-four-inch monitor. Its stand puts the bottom edge three inches above the desk at the lowest setting and eight inches at the highest. The panel is thirteen inches tall. So the top edge travels from sixteen to twenty-one inches above the desk. The table is thirty inches high, so the top of the screen can land anywhere from forty-six to fifty-one inches off the floor. With the cushion still in place, your seated eye height is forty-seven and a half. The stand's lowest position, forty-six inches, falls within the starting range, so you can try the existing stand without adding a riser. Remove the cushion, though, and your eye height returns to forty-five; the same stand would then start above eye level. The chair and screen have to be checked together.

Depth deserves the same check. A comfortable viewing distance is roughly twenty to thirty inches, about an arm's length. A monitor pedestal or a laptop riser eats six to twelve inches of desk depth all by itself. On a table only twenty-four inches deep, a deep base shoves the screen forward into your face, and no amount of height adjustment fixes distance.

Treat the top of the screen at or slightly below eye level as a starting point, then check the work you actually look at. On a large panel, an ultrawide or stacked screens, check the frequently used areas without lifting your chin or bending your neck; moving a window may help more than moving the whole display. If your work lives at the bottom of a terminal or timeline, check that area directly rather than lowering the screen automatically. Progressive or bifocal lenses can require a lower screen and some backward tilt so you can read without tipping your head back. Adjust for the actual task and confirm the result while working.

Then write four facts about the display itself next to your body numbers: its weight with the factory base taken off (put the bare panel on a bathroom scale, since every mount's limit refers to that), its width, height, diagonal and chassis depth, the spacing of the four screw holes on the back, and whether those holes are recessed or missing. Nobody can tell you whether an arm or mount fits until those, and a few facts about your desk, are in hand.

The next thing worth measuring is a real desk's finished range, thickness of the top included, against the seated and standing typing heights you just wrote down. The desk comparison is at ocdevel dot com slash ergo slash desks.

For today, take your four numbers. Feet flat and supported, shoulders dropped, arms hanging, elbows at about a right angle. Floor to elbow and floor to eye, seated, and then again standing in the shoes you actually wear. Write them at the top of a page you can find again. Everything after this is decided by those four lines.