Will an Iphone 4 sim card work for the IPhone 5?

I curently have the Iphone 4, and I am buying the Iphone 5 (AT&T) on Ebay. Will the sim card from my IPhone 4, fit into the IPhone 5 so I can automatically start using it?

It might. I know in my iPhone 4 there's no SIM card and I have AT&T. Just take it to the AT&T store and they will switch it.

You need to Convert Micro SIM Card into Nano SIM Card
here guide

No, the iPhone 4 has a Micro Sim and the iPhone 5 has a Nano Sim. You'll either need to buy a Sim cutter off of Ebay (in my case it didn't work), or you'll have to go to your service provider and pick up a new Sim card.

No because the are 2 different sims beacuse the iphone 5 has a smaller sim

will a a nano sim card for I5 work in an I4s?