How many minimum number of nand gates are required to realize xor gates?

As such an OR gate should do the job...but if the question is of using gates other than the simple OR, it should be a combo of NOR and NOT gates; where-in, the NOT gate comes after the NOR gate.

Factfully speaking:

The output of a NOR gate when fed to a NOT gate shall give you an OR gate.

cheers :)

Anish Murthy Airpula,

RF Design Engineer (F.A.E)

Ceramic & Microwave Products Group,

Dover Corporation Inc,

United States of America