[pbhjpbhj]

How do you know how many upvotes a comment has?

[drcube]

Aren't HN comments sorted in order of popularity by votes? Is the top comment not the highest upvoted?

I don't know, but this is what I've always assumed.

[nitrogen]

Last I heard (and I'm no authority on the subject), HN uses a sorting algorithm that incorporates many variables, including the age of the post, number of upvotes, reputation of the commenter, etc.