How to estimate the storage needed for a database?

I ran across this questions trying to dive into a computer measurements worksheet online and for the life of me could not figure it out. This is the question: Assume each record in a database requires 1Kib and there should be approximately 5 million records that need to be stored. Estimate the amount of storage needed in gibibytes for the database. Any help would be extremely appreciated because I'm completely lost on this question even though it sounds like it should be simple. Thanks in advance.