The Saarland, Berlin, Hamburg and Bremen are smaller than the average county, but especially the latter three have a bit of a special status because they’re essentially just cities.

The next-smallest one, Schleswig-Holstein, is more than 5 times larger than the average county. Bavaria, the largest one is more than 24 times as large as the average county.

I take the average here, because some US counties are absurdly large. The largest proper county, San Bernardino, is larger than 4 states combined.

The median county size btw is 5 times smaller than the average size. Only Bremen is still smaller than that.