User avatar dimension standards or specifications [closed]

Question

We have seen a user avatar will have different sizes on Facebook, Twitter, etc.

For example, Twitter has 3 different avatar sizes: 24x24, 48x48, 128x128; Facebook mainly has 50x50 and 180x180>.

I am wondering if there is a standard thumbnail size that a website should adopt, or it's all solely based on the design?

Thanks.

Answer 1

Like you say its just down to the design of your site. If in doubt, adopt the same resolution as a big player like Twitter, and allow users to upload a larger image which will give you the flexibility to show a larger version if someone clicks through to their profile.