Well since detective Conan Has a floating timeline, and we are still in the one year, where only a few months have passed
"Detective Conan operates on a floating timeline, which means there is a severe but unavoidable contradiction between the amount of time characters claim has passed and how much time has apparently passed according to the reader. These contradictions make it impossible to really determine when certain events in the current timeline happened exactly, since 20+ years of cases, seasons, and holidays are being crammed into "less than one year"
." ( http://www.detectiveconanworld.com/wiki/Timeline
Conan is 6-7
Shinichi is 16 - 17 years old and will remain
As far as I know in movie 1, The events take place around Shinichi's birthday, where ran almost gets killed by a bomb.
Since Conan movies are not considered Conan plot, therefore his age would be 16 - 17.
Some manga cases listed shinichi's age as 16 and in episode 3, shinichi said he was 17, so its all up to gosho.