Moving OS from hdd to ssd

[FlyingRooster]

hey guys so im building my first pc and im planning on investing in an ssd for the future but is it possible to transfer my OS (windows 7) fromm a mechanical hard drive to an ssd later?

 

[FlyingRooster]

alright thanks so would it cost another 100$ to buy windows 7 or if i buy it once can i put it on the ssd for free?

 

[FlyingRooster]

Alright thanks alot!

 

[FlyingRooster]

Best answer selected by FlyingRooster.