Stability Ball Sizing Tool

Find the right stability ball for your body and your goals

Tell us your height and how you plan to use it. We’ll recommend the optimal diameter, explain the firmness logic, and link you to current top-rated models.

Your Measurements

Adjust the slider and pick your primary use case. The recommendation updates instantly.

5’7″ 170 cm
4’0″ 5’0″ 6’0″ 7’0″
Primary Use Case
Your Recommendation
65
65 cm ~25.6 inches
Firmness Guidance
Firm — fully inflated

For desk use, inflate firmly so the ball holds its shape under body weight. Your hips should sit level with or slightly above your knees.

Why This Size

At 5’7″, a 65 cm ball positions your hips and knees at roughly 90 degrees when seated — the ergonomic baseline for desk work.

Fit Check
  • Feet flat on the floor
  • Knees at approximately 90 degrees
  • Hips level with or slightly above knees
  • No sinking more than 2–3 inches

This tool provides general sizing guidance based on height-to-diameter ratios used by major manufacturers. It is not medical advice. If you have specific health concerns, consult a physical therapist or clinician.

Sizing Chart

How your use case changes the ball you need

A stability ball isn’t one-size-fits-all. Your use case changes how firm the ball should be, whether you should size up, and what construction matters most.

Desk Chair

Inflate firmly to the full diameter. A firm ball holds its shape under sustained body weight, keeping your hips at the right height for ergonomic alignment. If you’re near the top of a height band, consider sizing up — sitting compresses the ball slightly, and a firmer/larger ball sits higher for better desk posture.

Core Workout

Use the base size with slightly less firmness. A ball with a small amount of give responds dynamically during crunches, planks, and stability exercises — that instability is what challenges your core. Sizing down slightly increases the challenge for advanced movements.

Physical Therapy

Use the base size with controlled, moderate firmness. Prioritize anti-burst construction, a textured non-slip surface, and slow-deflate materials. Clinicians typically avoid aggressive sizing — the goal is controlled support for rehab, balance training, and gentle mobility work, not maximum challenge.

Ball Size User Height Desk Chair Notes Core Workout Notes Therapy Notes
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