This question already has an answer here:
It says at naruto.fandom.com that Kakashi graduated at age FIVE after a year at the Academy. His teammates graduated at age nine a FEW YEARS AFTER. And then somewhere it says again that Kakashi was promoted chunin at age SIX and that was WITH HIS TEAM! But they were at the ACADEMY at the time! Then they say his last test to become GENIN was when he was placed under Minato with Obito and Rin. At the age NINE. After which they supposedly took their first Chunin Exam where Kakashi won against Gai and got promoted. But Kakashi was supposed to be chunin already. What. How. I'm so confused. SOMETHING has got to give for this to work.