There is really nothing in the picture but cock, balls, and leg. But based on the size of the balls, it looks like the cock is about 3 ball widths long. I therefore say about 6 inches long, about 5 inches around.

from that pic, looks around 6" as the angle is awkward, the tip is out of shot, & there is nothing in the frame to get any reference from.

7’5 to 8 inches but on photos penis can look bigger

At least 7.5”