There isn't a hard and fast rule on seat adjustments.
> [!tip] From Jack
> I typically teach the following for a [[Cessna 172]] or [[Piper Archer II]]:
> - Seat should be high enough to see a bit of the cowling
> - Seat should be forward enough that when fully depressing the rudder and brake, the knee has a slight bend
>
> Some people like to memorize how many 'rotations' of the height adjustment of a C172 is required for them, so they can easily reset it from all the way up or down.
For a look at proper seating in an airliner, checkout [this article](https://skybrary.aero/sites/default/files/bookshelf/4247.pdf).