The network address 192.168.10.0/24 has a subnet mask of 255.255.255.0, which provides 8 bits for subnetting. The formula to calculate the number of subnets is 2^s (s being the number of subnet bits), which in this case is 2^8 = 256. However, one subnet is reserved as the network address, and one subnet is reserved as the broadcast address, so the maximum number of usable subnets is 256 - 2 = 254.