Topic: How can I tell how much file is space is being used?

That’s right, though it’s pretty inconspicuous. In the account page, just under the “Upgrade or downgrade” label, is some gray text which shows your usage, like so: “You have x pages using xx MB.”

Topic: How can I tell how much file is space is being used?

I can see my upload usage next to the pages amount in the Account tab, up to the top left