Design systems already use tokens for colour, spacing and typography. Motion tokens apply the same idea to animation. They turn decisions such as "small elements move quickly and settle gently" into named values that every designer and developer uses.
A typical set includes durations (short, medium, long), easing curves (standard, enter, exit) and, increasingly, springs defined by stiffness, damping and mass. Springs are popular because they feel natural and handle interruptions well in code.
Naming matters. Names based on purpose, such as motion.enter or motion.emphasis, are easier to apply correctly than raw numbers. Keep the set small. If every component gets its own curve, the tokens stop doing their job.
Accessibility belongs in the tokens too. Define what happens when the user turns on reduced motion, for example shorter fades instead of large movement, so every component handles it the same way.
Tokens are usually stored in JSON and turned into CSS variables, Swift, Kotlin or JavaScript by a token build tool. Our free Motion Token Generator produces a starter set you can adapt.