Skip to Content
To Ergonomics is reader-supported. When you buy through links on our site, we may earn an affiliate commission. Read more.

What is My Office Chair’s Gas Cylinder Size?

my office chair's gas cylinder size

Most office chairs have a gas cylinder situated under the cushion of the seat. This cylinder allows you to adjust the height of the chair according to your preference and work with optimum comfort.

However, size matters when it comes to office chair gas cylinders, also known as pneumatic cylinders.

The size of cylinders ranges from 4 inches to 10 inches, with 5 inches being the standard size for most chairs. Many office chairs have a universal gas cylinder.

But to guarantee a smooth upward and downward mechanism of the chair, it is always preferable to measure the size of your cylinder before you replace it with a new one.

If you have taken over an office chair refurbishing project, and it requires you to replace the cylinder with a new one, keep reading.

Are All (Office Chair) Gas Cylinders The Same Size?

Office Chair Gas Lift Cylinder-Office Chair Replacement Parts

Yes, most office chair gas cylinders are the same size, measuring about 5 inches. The only significant difference between cylinders is the maximum height they enable the chair to go up.

An office chair pneumatic cylinder is essentially made up of two parts—the gas spring (the top part) and a column (which is the lower part).

Gas Spring

RiYii 8" Long Stroke Adjustable Office Chair Gas Lift Cylinder

The gas spring measures about 1.1 inches. This part of the cylinder holds nitrogen gas and lubricant oil.

The button or lever that is pushed to make the chair elevate or go down is present at the top end of this spring. This is attached to the bottom of the chair’s seat.

The piston is situated on the lower end of the gas spring. The piston moves in and out of the cylinder, which facilitates the movement of the chair in the upward and downward directions.


gas cylinder - column

This is the lower part of the gas cylinder that measures about 2 inches in diameter. This part is attached to the casters, which are present on the base of the chair.

Besides these two crucial parts, you need the correct bearing kit to hold every part of the cylinder in place. This kit usually consists of a plastic bearing, a rubber bumper, a retaining clip, and two metal washers.

Most bearings kits are universal for office chair gas cylinders and must be installed correctly for safe and efficient usage of the cylinder.

How Do I Measure My Chair Gas Cylinder?

How to Measure a chair Gas Cylinder for replacement install/remove

Before you replace your cylinder with a new one, you have to determine whether the manufacturer has used a standard cylinder for your chair. Here are some easy steps to measure your cylinder.

  1. Tilt your chair upside down or tip it over on the front edge of the seat.
  2. Cover your flooring with an old cloth, rag, or newspaper to avoid any damage or grease spots.
  3. Remove the base of the chair on which the wheels are attached.
  4. Take a screwdriver and insert it into the fold of the clip that is present beneath the base.
  5. Twist the clip and push it upward with the screwdriver to make it pop out.
  6. Remove the washer.
  7. Gently pull the base off the chair.
  8. Remove the bearing parts like the rubber bumper, washer, and bearing’s exterior ring.
  9. Remove the plastic telescope cover that encloses the cylinder. This will reveal the gas cylinder.
  10. Now using a measuring tape, measure the body of the gas cylinder. Place one end of the measuring tape right below the chair’s mechanism. Bring the other end of the tape to the end of the gas cylinder. You’ll need to stop right before the piston rod.
  11. The chair’s mechanism holds an extra inch of the gas cylinder. Add this to your measurement.

For example, if your cylinder measures 4 inches, you will add an extra 1 inch and place an order for a 5-inch cylinder.

How To Choose The Right Cylinder For My Office Chair?

MySit Office Chair Gas Lift Cylinder Replacement

Unless you have the right cylinder for your office chair, you will be unable to set the chair at the proper, desired height.

While sitting, your legs should sit flat on the ground, with your back straight and your knees bent at an angle of 90 degrees. As each individual’s body size and height differs, the cylinder helps adjust the chair until all the critical sitting factors are met.

To choose the right cylinder for your office chair, be mindful of the following points:

  • Although the size of the cylinder is universal across most popular and commonly bought chairs, different cylinders may allow different heights of the seat. Determine this before purchasing the chair.
  • Sit on the chair and ensure that the cylinder enables you to sit with your knees at the right angle, thighs parallel to the floor, and your feet flat on the ground.
  • For women who wear heels, wear shoes with different heel sizes to determine the maximum and minimum height the chair can accommodate.
  • The size of the cylinder depends on the height of the user of the chair. For example, if you are less than 5’4″ tall, a 4 inch cylinder would be the perfect setting. If you are above 5’4″ but below 6’2″, go for a 5 inch cylinder, and if you are taller than 6’2″, go for a 6 inch cylinder.


A gas cylinder is one of the most overlooked but essential parts of an office chair. Without a proper gas cylinder, your office chair can lose its capacity to adjust.

This can cause an uncomfortable sitting experience, a compromised posture, and various other health implications.

The right-sized cylinder will ensure the maximum efficiency of the chair.