Correct Sitting Posture at a Desk: What It Is and How to Hold It

What is correct sitting posture?

Correct sitting posture is a neutral posture: one where your joints are naturally aligned, so muscles, tendons and the spine carry as little strain as possible. OSHA's computer workstation eTool says working in neutral positions reduces stress on the musculoskeletal system and reduces the risk of developing a musculoskeletal disorder.

OSHA's description of neutral sitting at a computer:

• Head level, facing forward and balanced, generally in line with the torso.
• Shoulders relaxed, upper arms hanging normally at the sides.
• Elbows close to the body and bent between 90 and 120 degrees.
• Hands, wrists and forearms straight, in line and roughly parallel to the floor.
• Back fully supported, with lumbar support when upright or leaning back slightly.
• Thighs and hips supported and generally parallel to the floor.
• Knees at about the same height as the hips, feet slightly forward.
• Feet fully supported by the floor, or a footrest if the desk is not adjustable.

You can check how your own desk measures up against this list with the workstation self-assessment. It takes a few minutes and points to the adjustments most likely to help.

Is there only one correct way to sit?

No, and this is the part most posture advice gets wrong. OSHA's eTool states there is no single correct posture or arrangement that fits everyone. It also defines four reference postures that all count as neutral:

Reference posture	Description (OSHA)
Upright sitting	Torso and neck approximately vertical and in line, thighs approximately horizontal, lower legs vertical
Standing	Legs, torso, neck and head approximately in line and vertical, feet slightly apart
Declined sitting	Thighs sloping down, buttocks higher than knees, angle between thighs and torso greater than 90 degrees, torso vertical or slightly reclined
Reclined sitting	Torso and neck straight and reclined between 105 and 120 degrees from the thighs

In other words, correct sitting posture is a range, not one pose. A chair and desk that let you move between these is better than one that locks you into the "perfect" upright position.

Why does changing position matter as much as posture?

OSHA is direct about this: regardless of how good your working posture is, working in the same posture or sitting still for prolonged periods is not healthy. It recommends changing your working position frequently:

• Make small adjustments to your chair or backrest.
• Stretch your fingers, hands, arms and torso. Our 5-minute stretch routine for office workers shows how.
• Stand up and walk around for a few minutes periodically.
• Do some tasks standing, such as reading, phone calls or meetings.

HSE's work routine guidance says there is no legal rule on how long or how often breaks should be, but that short, frequent breaks are better than longer, infrequent ones. Its example: 5 to 10 minutes every hour is better than 20 minutes every 2 hours. Breaks should let you get up and move, or at least stretch and change posture.

How do you adjust your chair for correct sitting posture?

The chair sets everything else, so start here. These steps combine CCOHS's chair adjustment guidance with OSHA and HSE.

1. Set the seat height. CCOHS suggests standing in front of the chair and setting the highest point of the seat just below the kneecap. Sit down with your feet flat on the floor. OSHA describes the right height as the whole sole resting on the floor, with the back of the knee slightly higher than the seat.
2. Check the seat depth. You need a gap between the seat's front edge and your calves. CCOHS uses a clenched fist, about 5 cm (2 in). HSE's posture guide gives 2 to 3 cm. Either way, the seat should support most of the thigh without pressing into the back of the knee.
3. Fit the backrest to your lower back. Move it up or down and forward or back so the curve fits the hollow of your lower back. OSHA recommends a backrest that can recline at least 15 degrees from vertical and lock or be tension-adjusted.
4. Set the armrests. Sit upright with arms hanging, elbows at about 90 degrees. Raise the armrests until they barely touch the undersides of the elbows. CCOHS says to remove the armrests if they lift your elbows even slightly at their lowest setting.
5. Tilt the seat forward or back if you prefer. CCOHS treats this as personal preference.

If the desk is fixed and too high

This is where correct sitting posture most often breaks down. Raise the chair until your elbows are about level with the work surface, then add a footrest so your feet are supported. CCOHS recommends an adjustable footrest that supports both feet. If your legs no longer fit under the desk, the desk is too low for regular use. More on this in our ergonomic desk setup guide.

Where should your arms and hands be for good sitting posture at a desk?

Posture problems often show up in the arms first. OSHA's keyboard guidance asks for elbows at about keyboard height, hanging comfortably at the sides, with shoulders relaxed and wrists that do not bend up, down or sideways.

Two common faults:

• Keyboard too low. You type with your wrists bent upward.
• Keyboard too high. You raise your shoulders to lift your arms, which builds tension in the neck and shoulders.

HSE adds that the mouse should be in line with the elbow, and the screen and keyboard should be central so you don't twist your back.

Where should your head and eyes be?

Your head weighs the same whether it is balanced or not, but balanced costs less effort. OSHA says a monitor placed too high makes you tilt your head back and fatigues the neck. A screen too far away makes you lean forward and lose the backrest's support.

Put the top of the screen at or slightly below eye level, about an arm's length away. Our guide to ideal monitor height explains the details, including what to do with bifocals.

What gets in the way of proper sitting posture?

From OSHA's chair and keyboard hazards, these come up again and again:

• Perching on the front edge of a seat that is too high, so the backrest gives no support.
• Feet dangling because the chair was raised to reach a high desk without adding a footrest.
• Seat pan too deep, pressing into the back of the knees of shorter users.
• Armrests too high, keeping the shoulders raised.
• Armrests too wide, pulling the elbows out from the body.
• Clutter under the desk that stops you moving your legs.
• Laptop on the desk with no separate keyboard, forcing the head down.

Can you assess sitting posture objectively?

For office work, a checklist plus a quick look at the person working is usually enough. For a more structured score, ergonomists use observational methods such as RULA, which rates upper-body posture during seated tasks. Our RULA assessment guide explains how it works.

ViveLab's AI ergonomic assessment can estimate a RULA or REBA score from a phone photo or video, with processing done on your device. It is an AI-assisted estimate, and a trained assessor should review the scores before you act on them.

When is poor posture a health concern?

Aching that builds during the day and fades overnight is a common early signal that something about the setup or the work pattern needs attention. This article is general information, not medical advice. If you have persistent pain, numbness, tingling or weakness, see a clinician. Our guide to repetitive strain injury covers upper-limb symptoms in more detail.

Next steps

Correct sitting posture comes from a well-adjusted chair, a desk and screen that fit you, and regular movement. Run through the workstation ergonomic assessment, make the chair adjustments above, and set a reminder to change position regularly. Then read our full computer workstation ergonomics guide to cover the rest of the desk.