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How Wide Should an Office Chair Seat Be?

How Wide Should an Office Chair Seat Be?

If you work in an office setting, sitting in an office chair is probably where you spend most of your days. Over time, the lack of movement and poor posture can cause spinal misalignment and back pain. This is easily remedied by proper posture and a properly fitting office chair.

The question you might be asking is how wide should an office chair seat be. The most commonly advised width of an office chair is 17 to 20 inches. This is enough to provide proper support for your entire spinal and pelvic area while also allowing a 2 to 4 inch gap between the back of your knees and the edge of the chair.

The longer you sit in an office chair, the better your posture should be for the long term comfort of your back. Pinched nerves and strained muscles can happen with a slouched or leaning posture. Additional ways to help improve your posture include lumbar support, shoulder support, and headrests.

Most office chairs do not include many options to adjust their size, while others do. If you have a choice, always look for an office chair that allows you to adjust the seat width, back height, lumbar support location, and more. As your body adjusts to this new chair and your posture improves, your back pain and fatigue will be reduced or eliminated.

How Wide Should an Office Chair Seat Be for Comfort?

Finding the right office chair to fit your unique body shape and size is important. Especially if you spend several hours sitting in the chair daily. Over time, a poorly designed or improperly fitting chair can lead to poor posture and, as a result, severe back pain.

Ergonomic Office Chair

Poor posture, such as slouching or sitting at an angle, can cause muscle and tendon strain, pinched nerves, and more. This can lead to immediate or chronic back pain in people of all ages. As time goes on, this back pain can become debilitating, making it much more difficult for you to sit in a chair for long periods.

Ergonomic chairs as well as standard office chairs that fit your body shape properly are extremely popular. In today’s office chair market, you can find chairs with lumbar support, tall backs, seat width adjusters, headrests, and more. This all helps facilitate better posture and less back pain, even if used for hours at a time.

The best width of an office chair should be at least 17 inches, but no more than 20 inches wide. This allows you to sit fully on the seat with your entire body supported. The back of your knees should be 2 to 4 inches away from the edge of the seat. This prevents the pressure of your legs against the chair from cutting off circulation to your lower legs.

Adjusting the armrests can also help. By providing support for your elbows, you can take additional strain off your upper back, shoulders and neck.

How Should an Office Chair Fit?

If you have an adjustable or ergonomic office chair, there are various ways it can be adjusted to fit your body. You should always take the time to adjust the chair so that it feels comfortable to sit in. If you have poor posture, sitting in an ergonomic chair that encourages proper posture may be uncomfortable at first. In this case, always try to use the chair slowly at first.

Lumbar Support

Gabrylly Ergonomic Office Chair with Lumbar Support

Many office chairs include lumbar support. This may be in the form of a small pillow you can place at your lower back, just above your waist. It provides support for your lumbar area and gently supports the natural curve of your spine.

Chair Height

Adjusting the chair height is important. You want to be able to keep your feet flat on the ground when sitting, and your knees bent at a 90-degree angle. This helps align your pelvis, which in turn reduces muscle strain in your hips and spine.


Ergonomic Office Chair

Ensure your arm rests can be used comfortably. You want them to be at the same height as your elbows when you are sitting with proper posture in your office chair. Armrests that are too low will put strain on your shoulders and upper back.


Some office chairs include a higher-than-usual back with a headrest. The headrest should be adjusted to support your head and neck when you are seated comfortably with proper posture. This helps keep the entire spine aligned properly.

How to Adjust the Width of a Chair Seat

Many office chairs, especially those being marketed as ergonomic, will have various knobs and levers to adjust a series of components. This very often will include the seat width itself. By adjusting the placement of the back of the chair, you can instantly add more space to the seat.


Big and Tall Office Chair 400lbs Desk Chair

When sitting in the office chair, you want to sit in the chair with your back against the back of the chair. But you want the backs of your knees to be around 2 to 4 inches from the front edge of the seat. If the backs of your knees are right against the chair, blood circulation can be restricted to your lower legs.

  • Find the adjustment lever or knob. It is normally on the underside of the seat close to the back rest. It’s most often found as a lever, though a large knob may be possible.
  • Slide the backrest further away or closer to the seat. Adjust the width of the seat so that you can fit comfortably with 2-4 inches of space between the chair and the back of your knees.
  • Test the placement by sitting in the chair. Don’t be afraid to sit in the chair a few times to test the adjustment and see if it fits you comfortably.
  • Adjust as needed for the perfect fit. If the chair does not fit, keep adjusting until it does. While it might take a few minutes, adjusting the chair properly at the beginning will make sitting in it long term much more comfortable for you.

Why Does Office Chair Seat Size Matter?

B2C2B Leather Executive Office Chair

Sitting in an office chair that does not fit your body can be very uncomfortable over time, especially if you need to spend several hours in the chair daily. The more you use the improperly sized chair, the worse your posture can get. As a result, you will notice pain and discomfort in your legs, hips, spine, and shoulders.

You might also notice numbness or a tingling sensation in your lower legs or feet when sitting for long amounts of time. This can be due to an office chair seat that is not the right size, and is instead creating pressure points on your legs and hips. This can reduce blood circulation around your body and cause potentially dangerous health problems.


Dancing Wolf Office Chair Ergonomic

From a fully adjustable ergonomic office chair to the standard chairs that only offer one or two adjustments, you should always adjust the chair to fit your body as best you can. Sitting in an office for hours per day is not uncommon, but over time it can lead to physical discomfort and health problems.

You might feel perfectly fine sitting in a new office chair at the start, but if it is not adjusted to your body you will notice aches and pains starting to develop over time. If your posture is not improved, these minor aches and pains can become more serious health problems with your spine, muscles and blood circulation.

Always be sure to take a bit of time to adjust your new office chair to fit your body. Adjust the placement of the lumbar support, the height of the backrest, the width of the seat, and the height of the seat from the floor. If applicable, don’t forget to raise or lower the armrests to a comfortable height, as well as the headrest.