This free time tracking tool shows the times your computer has been active during the last 3 weeks, with no previous setup required. The software doesn't need to run in the background, because Windows OS tracks logon and logoff/standby times (working hours) by default, and the program analyses it. PC On/Off Time is Freeware. Your working time is displayed graphically. PC On/Off Time also shows the working time of all computers on your network.