Easy Way to Subnet

Write out a chart with 10 columns and about 10 rows. On the top right hand corner write the number 1, then to the left double it to 2, then 4, then 8 all the way up to 128.

On the second from the top left hand row write 128 then add 64 to make 192 then add 32 to make 224…all the way down to 255.

Here is the chart written out in full:

http://www.subnetting-secrets.com/subnetting_cheat_sheet.html