Exercise Ball 60-65cm vs 70-75cm: How to Pick Your Size
By Casall | Published: 2026-11-03
Category: Guias Práticos
Use your height to choose between a 60-65cm and 70-75cm exercise ball, then inflate and check the fit for desk sitting and training.
Quick answer
Choose the 60-65cm ball if you are under 175 cm tall; choose the 70-75cm ball if you are over 175 cm. Then inflate to the size that lets your hips and knees sit at about 90 degrees when you sit on it.
Why height is the starting point, not the final check
Height gives you the right size range, but your torso and leg proportions determine the final fit. A 175cm person with long legs may feel more comfortable on the larger ball, while a 178cm person with a short torso may prefer the smaller one.
For desk sitting, the ball should let your thighs be roughly parallel to the floor and your feet rest flat. If your knees drop below your hips, the ball is too small; if your hips drop below your knees, it is too large.
What changes when you move from 65cm to 75cm
The 70-75cm ball raises your seated height by about 5-10cm, which can make it a better match for taller desks or longer legs. It also feels less stable under you because the larger surface allows more movement, so it may suit experienced ball users better than beginners.
The 60-65cm ball is easier to control for most home workouts and takes up less floor space. It is also the safer default if you are near the 175cm boundary and unsure which way to go.
How to choose and set up your exercise ball
- Measure your height without shoes: Stand against a wall and mark the top of your head. Use the result to pick the size range: under 175 cm, start with 60-65cm; over 175 cm, start with 70-75cm. Measure once and write it down so you are not guessing at the boundary.
- Inflate gradually and check the diameter: Inflate the ball in stages, measuring across the middle after each session. Stop when it reaches the lower end of your chosen range, then let it sit for a day before adding more air. A ball that feels firm on day one often grows overnight; leave room for that expansion.
- Sit and check the 90-degree rule: Sit upright with feet flat. Your hips and knees should both be near 90 degrees. If your knees are higher than your hips, add air; if your hips are lower than your knees, deflate slightly. Adjust by air pressure, not by swapping sizes, unless the ball is far outside your height range.
- Test the ball at your desk before a full day: Spend 10-15 minutes seated before committing to longer desk sessions. Check that your forearms rest comfortably on the desk and your feet stay flat without sliding. If you have to reach up or slouch down, revisit the ball size or your desk height.
- Recheck firmness monthly: Exercise balls slowly lose air. Measure the diameter again each month and top up if it has dropped below your target range. A soft ball changes your seated posture and reduces the stability challenge.
Product facts
- Exercise Ball 60-65cm - Light Cashmere: Anti-burst technology lets air escape slowly if punctured. You get a safer failure mode during desk sitting or strength work, but you still need to inspect the ball regularly.
Exercise Ball 60-65cm - Light Cashmere - Exercise Ball 70-75cm - Black: Recommended for users over 175 cm tall. This gives taller users a clear starting size for both seated desk use and full-body stability training.
Exercise Ball 70-75cm - Black
