Clear all formatting between the last cell and the data. 1  Do one of the following: To select all columns to the right of the last column that contains data, click the first column heading, hold down CTRL, and then click the column headings of the columns that you want to select.
Find your IP range by examining your subnet mask. Most likely, if you are using a simple home network, your IP address begins with 192.168.0 and your mask is 255.255.255.0. This mask means that the address range 192.168.0.1 to 192.168.0.255 is available for assignment in your subnet. Show Comments.
To calculate the Network ID, you simply take any IP address within that subnet and run the AND operator on the subnet mask. Let's take an IP address of 10.20.237.15 and a subnet mask of 255.255.248.0. Note that this can be and often is written in shorthand as 10.20.237.15/21 because the subnet mask length is 21.his means there are 2^11, or 2,048, maximum hosts in the subnet and the last IP in this subnet is 10.20.239.255. You could compute this quickly by seeing there are three zeros in the third octet, which means the third octet of the IP address can have a variance of 2^3, or 8.