What sort of skating are you doing?
To summarise wheel size and durometer roughly:
A larger diameter wheel gives a smooth roll. Like a heavier object, it has more momentum and will maintain it’s top speed without much help. Like a heavier object, it does require more PUSH to get it up to top speed.
A smaller diameter wheel is easier to change speed – for manoeuvrability this is king. You’ll see many aggressive (park) wheels up to 60mm wheels.
Remember that a larger wheel will require a taller frame, putting you further off the ground – ‘ride height’ is another factor in skates and stability.
To summarise durometer, or wheel hardness:
The durometer rating is a scale, where the higher number is harder and the lower number is softer.
A harder wheel goes faster, but actually compromises some grip. If skids and slides are your thing, you need a hard enough wheel to get some controlled slide.
A softer wheel will grip around corners better, and acts like a little bit of suspension, too. Softer wheels are often more comfortable, but won’t be as outright fast or as easy to slide on.
Both these concepts have different parameters for quad (roller) skating, recreational inline, speed skating or other forms of skating.
Let us know a bit more about your skating, and we'll help recommend a wheel for you!