"Juvenile offender" is child below the age of?

Juvenile courts "WHO considers children to be human beings below the age of 18 years. They try offences committed by juveniles (below the age of 18 years.)" S. 27Cr. P.C. Offence means any act or omission made punishable by any law (S.2(n) Cr.P.c. &(S.40,LP.C.).