How will i be able to use my micro sim card from my iPhone 4s, in the nano sim card tray in the iphone 5?

No

http://www.apple.com/iphone/compare-iphones/

Says it is not compatible with the 5

Nano SIM card?

You can't. The nano SIM is 15% thinner compared to its previous two generations, so even if it is cut in the same size, the thickness would be different, meaning the cut micro SIM cannot fit into the nano SIM slot.

Thanks, appreciate the explanation

Thickness is not an issue. It can be sanded down using fine grit sandpaper.

Yeah, I guess you're right...cutting a micro sim down, then sanding it to the proper thinkness is a heck of a lot easier than just getting a nano sim. Be sure & recommend that to all of your friends. 😎

nano sim and micro sim are completely different. I don't think they will work.

Not really. Micro sim and nano sim are the same thing. Only difference is size and thickness. Other than that their the same thing.

Yeah but sanding it might destroy the electronics in the micro sim so why would you do that?

The chip is the same size. As long as you don't sand down all the way to the chip your completely fine.

That still seems like a downright stupid way to deal with it considering most carriers will provide a new SIM for free or a minimal charge...

I'm assuming that carriers and the Apple store have a way to transfer data for you.

On ebay they have nano sim cutters..

There is no data stored on the iphone sim card.

They have lots of junk on ebay.

They had iPhone 5 cases on e-bay last year at about this time. Too bad they didn't fit anything that was ever released.