How many GB is my iPhone 4s? - 1

Ok little confused, I thought I'd bought the iphone 4s 8/16gb but checking through my phone today I've found the usage part. It says 22.9gb available and 5gb used. Can anyone enlighten me?
Also says capacity is 27.9 gb. Does this mean its the 32gb but thats it pre installed software means available is the above, it's what I've been lead to believe.

Your hot

Sounds like you have the 32 GB model.
Then you have to allow for the software so it takes it down a touch.

Mine is the 16GB but my Capacity is 13.3GB

Yes, you have a 32GB model.

It is a 32gb model and the OS takes up around 4 gigs of space. That is why it says you have 27.9 free.