From NFS site:

> Currently we are not tracking (and hence not billing for) extra bandwidth usage. This is subject to change at any time.

What do you do if your small static site gets suddenly HN audience? Do you then pay thousands for the bandwidth?

For simple static sites, I always look at the egress rates and bandwidth caps. For example if you have Wasabi+Cloudflare, then you know the pricing before hand. Wasabi doesn't have egress fees even if Cloudflare were to redirect all traffic for a while to your files.