How old is Naruto in Boruto series? Naruto failed the graduation exams three times at the academy before he could graduate (performing the transformation/clone jutsu).

Does this mean he is three years older than his comrades from the academy? So, in Boruto, what would his current age be?
Let's say after the end of The Fourth Ninja World War, Naruto is 17 years old. Then, in The Last: Naruto the Movie, it's stated that the event occurred after 2 years.  You can rever to this https://en.wikipedia.org/wiki/The_Last:_Naruto_the_Movie.

Then sure, Naruto married after that, let's say it takes several months for marriage preparation, and Naruto married at the age of 20, and Boruto is born 1 year later at Naruto age 21.

Now in Boruto: Naruto Next Generation series, Boruto is already graduated from the academy and as a gennin. The common age of a ninja who graduated from the academy is 12 years old. Many things happen after Boruto become a gennin, and let's say his age is 13.

So Naruto's age now in Boruto: Naruto Next Generation series is about 21 + 13 = 34 years old.