Circular Needle Sizes vs. Straight

After I complete my current project, a sweater/jacket I want to try using circular needles. With my current project for instance, I needed to use 14-inch needles for the back of the sweater and found them somewhat annoying as it would poke me in my shoulder while knitting. After I switched to shorter needles for the fronts all was well, but I still want to give the circular ones a try.

My question is: How does one determine the length of the cable on the circular needle for a specific number of stitches. I’ve noticed the Addi-turbos start at something like 12’ cable on up to very long. Is their a simple ‘rule-of-thumb’ for this?

Thanks for any info as I don’t want to purchase needles I may never use.

If you want to use them for knitting back and forth, the longer the better, really. A 29 or 32-inch cable is good for back and forth as well as bodies of sweaters and such.

A 16" needle is a must for hats.

This is where an interchangeable set like the KnitPick Options comes very much in handy. You can change the cable length to suit your needs, and the tips are comparable to Addis.

I appreciate the information to my question. This will save having the same size needle with different length cables. I will check out the Options again. Thank you so much.