Ergonomic Desk Setup: Chair, Keyboard and Screen Heights

What you need to know first

Good posture at a desk is mostly geometry: the chair, the keyboard and the screen at the right heights relative to you. Set them in order, chair first, because everything else depends on where you sit. The guidance below follows OSHA's computer workstation eTool.

Step 1: Set the chair

• Height: your whole foot rests on the floor and the back of your knee is slightly above the seat. If the chair will not go low enough for the desk, raise the chair for the desk and add a footrest.
• Depth: the seat supports your thighs without the front edge pressing behind your knees.
• Lumbar support: adjusted to the curve of your lower back. No lumbar support? A rolled towel or a removable cushion helps for now.
• Armrests: only if they adjust to support your forearms with shoulders relaxed. Otherwise remove them.

Step 2: Set the keyboard and mouse

Keep your elbows close to your body and your wrists straight, not bent up, down or to the side. Put the mouse right next to the keyboard so you do not reach.

Step 3: Set the screen

• Distance: at least 20 inches (50 cm) from your eyes; OSHA gives 20 to 40 inches as the preferred range.
• Height: top of the screen at or slightly below eye level.
• Position: directly in front of you, so your head, neck and body face forward.

With a laptop, you cannot meet the keyboard and screen rules at once. Raise it on a stand and add a separate keyboard and mouse.

Step 4: Fix the light

Put the screen side-on to the window, so daylight does not glare on it or come from behind it. Add a desk lamp aimed at your work, not at the screen.

Step 5: Move

No setup makes sitting still for hours comfortable. Stand up and move every half hour or so. If you want to work standing for some of the day, see standing desks for small spaces.

In a small space

• A desk around 24 inches (60 cm) deep gives a monitor enough distance; shallower desks suit a laptop on a stand.
• A clamp-on monitor arm frees desk depth and needs no wall fixing.
• A dining chair works for short sessions with a lumbar cushion and a footrest if needed.

More on fitting a desk into a small room is in how to build a home office in a small bedroom and best office chairs for small spaces.

Common mistakes to avoid

• Setting the desk first and the chair to match. Start with your feet on the floor.
• Laptop flat on the desk all day.
• Screen to one side, so you twist all day.
• Monitor on top of a computer case or a stack of books that is too tall.

What to do next

Check each step with a tape measure this week, then adjust one thing at a time.

Check your setup in two minutes

• Feet: flat on the floor or a footrest.
• Knees: roughly level with or slightly below your hips.
• Back: supported by the chair, with a cushion at the curve of your lower back if needed.
• Elbows: close to your sides, bent at about a right angle, forearms level.
• Wrists: straight, not bent up or down while typing.
• Screen: an arm's length away, top at or just below eye level.

Working from a laptop

A laptop on a table forces you to choose between a good screen height and a good keyboard height. The fix is a laptop stand plus a separate keyboard and mouse. If you cannot buy them yet, raise the laptop on books for video calls and long reading, and lower it for typing.

Move often

The best posture is the next one. Change position, stand up and walk during calls, and look away from the screen regularly. A short break every half hour does more than any one perfect setting.