There's no guide anywhere as to the grades of each badge, but you can guess the hierarchy of most by right-clicking and choosing "Open Image In New Tab" where you can see the pip name.
For example stachelzelle has Article.png; the base level, at least one product blog post made - Frank21 has Article_1.png, the next level up. Dunno how many posts you've made Frank, but a few I'm sure. Mine is Article_4.png, I've got around 150 posts to the blog (133 currently active in one Mega, others scattered elsewhere). So the actual numbers where you transition are unknown, but you can get a rough idea. I know I went from rank 4 to 5 somewhere around 320,000 points, and I've seen a few in level 6 with a bit over 600,000.
Secret: you can see some of the "new" badges here:
https://zonegfx.com/wp-content/uploads/2021/05/
Fiddle with the URL dates and you can discover lost site media from years gone by 🙂