How big is each star?

It would be impossible to list the sizes of all known stars. But for a great brief presentation of the range of star sizes, go to the link below. Stars can range in size from newtron stars, roughly 20 to 40 km in diameter, to the largest know star in Canis Major. It is VY CMa, with a size of about 2,100 solar radii (a radius 2100 times the length of our sun's radius). That's a lotta gas.