It's ambiguous.

Mass-wise, it's a more or less smooth transition from the jovian planets to low-mass brown dwarfs.

Radius tends to get influenced in a somewhat complicated way by mass, and as far as the gas giants go, hotter planets tend to be larger than cooler ones. Measurement errors make this subject to change, but a hand-wavey figure would be ~2x Jupiter at the upper limit.

An honorable mention goes to mamajek's object due to its giant ring system.