It is 1mm diameter
Broomstick knitting needles are the size of a broomstick handle. That would be approximately 2.75 inches in circumference or about 7/8ths of an inch in diameter. This would be a US 42 size (I believe), or a 22.0 to 22.25mm size, needles.
A US knitting needle size 6 would be equivalent to a UK knitting needle size 8, or a 4mm.
US size #3, UK size #10
size 6
Diameter
20mm knitting needles are needles that are 20mm in diameter. They are also known as US size 35 needles.
it means you have either added yarn overs or dropped stitches. it might mean you are a beginner or it might mean you are knitting lace and want the holes. or that you are knitting on needles slightly larger than you would use for a not holey fabric. P.S.: You are supposed to have holes in your knitting! The hole size is because the size of the needle. (ex: large size needles=large hole, small needle= small hole) Understand now?
yup. the bigger the needle, the bigger your stitches. likewise, the smaller your needle, the smaller your stitches. simple really.
regulation size is18 inches in diameter
The size of a pin head is roughly two mm in diameter. The size of a sewing needle head is roughly five mm in diameter.
It depends on what you mean by a certain size circle. If the certain size is the diameter, then the answer is 54 inches. If the certain size is the radius, then the answer is 108 inches. If the certain size is the circumference, then the answer is 54 / 3.14159 or about 17.19 inches
If they don't have a recommended needle size on the label, I would check with the maker. The only other option is to swatch it with different sizes until you like the way it looks.