Kakashi is 34 in Naruto.
Kakashi’s birth date is November 8, according to the manga profile. He was born during the Second War Era, 34 years before Naruto TSRP (68). In volume 40 of the manga he says that his next birthday will be on a Monday if we assume no leap year is occurring. And just for fun I checked 2020 on WolframAlpha and found out to my surprise there’s no leap year that year! So happy 35th birthday Kakashi or 7th for you October babies!