Trackball Ball Sizes and Replacement

By Xah Lee. Date: . Last updated: .

Where to Buy Replacement Balls?

Sometimes you can buy replacement balls designed for the device, but typically they are way expensive and not worth it.

Logitech M570 trackball replacement ball (34 mm). Buy at amazon

Logitech Trackman Marble replacement ball-s
40 mm balls for trackball. Buy at amazon
plank keyboard trackballs 39200-s
Planck KeyboardKensington Orbit Trackball with Scroll RingLogitech Trackman Marble Mouse Review. 〔image source https://www.reddit.com/r/Trackballs/comments/3ahtsk/interchangeable_balls/

Billiard Ball Sizes

pool table balls
American-style pool table balls. 57.15 mm (2 1/4 inches) billiard balls

The American-style pool ball, at 57.15 mm (2 1/4 inches), is the most easy to find.

You'll also find mini 1 3/8 inch (34.925mm) ones.

Crystal “Healing” Balls

Quartz balls are most beautiful.

Few things to be aware:

  1. heavy ball may wear down the ceramic bearings in the trackball socket.
  2. Clear glass or polished surface may not track well.
  3. The advertised size is often inaccurate. (because for decorative purposes, size precision isn't important) Be sure to look for size discrepancies in buyer comments.
rose quartz 1.25 inch sphere ball-s
Buy at amazon
purple crystal ball 40mm 24581
40mm Asian Rare Natural Quartz Magic Crystal Healing Ball Sphere Purple Buy at amazon

note: these may not be machine made, so, may not actually fit well.

Kensington Orbit Trackball scroll ring quartz ball-s
lighting effect with a quartz ball, more beatiful than can be captured by a photo. 〔https://www.reddit.com/r/Trackballs/comments/2y0gr9/quartz_crystal_ball_replacement_part_1/
Kensington Orbit Trackball scroll ring ball 64446-s
ball of Kensington Orbit Trackball with Scroll Ring
quartz ball 68851-s
quartz ball.

Large Marbles

marble size chart 70321 jff
〔image source https://www.moonmarble.com/

some large marbles will work for smaller trackballs.

jumbo 2 inche marbles but actually ~44.45mm or so inches Buy at amazon

42 mm marbles. Buy at amazon

42 mm marble Buy at amazon

35mm marble Buy at amazon

Note that the marbles may not come in exact size.

Inche to Millimeter Conversion Table

Trackball Physical Sizes Comparison


Trackball Sizes Comparison