Sorry there is not a temperature rating. Most manufacturers do not have temperature ratings for their garments or footwear due to the number of factors that affect how warm a garment may keep you.
This information was not in the item description because the manufacturer does not state it on the tags... the jacket itself is very nicely made, instant warmth when put on. very versatile. I am confident my little guy (6-years) will be warm in the wet single digits of dead winter with proper under clothing, and hats/mitts. Great coverage around the neck with the zipper and velcro not rubbing agains the skin and completely doable by younger hands. Hope this helps.