Windows 8/8.1 and Windows Server 2012/2012 R2
Microsoft's official Windows 8.1 Support Lifecycle Policy treats Windows 8.1 as if it were a service pack for Windows 8. That means the lifecycle calculations start when Windows 8 shipped, in 2012.
Support for the original release of Windows 8 ended "two years after the General Availability of the Windows 8.1 update," or October 18, 2015. The same policy applies to Windows Server 2012 and 2012 R2 (equivalent to Windows 8.1).
Most PCs that included a preinstalled version of the original release of Windows 8 have long since disappeared from retail channels. For the dwindling population of PC users still running Windows 8, a free upgrade to Windows 8.1 is available through the Windows Store.
Mainstream support ends: January 9, 2018
Extended support ends: January 10, 2023
Windows 7 Service Pack 1 and Windows Server 2008 R2
This is currently the most popular release of Windows, and promises to hold that top spot for a long, long time. The following support dates require that you install Service Pack 1 (Windows 7 RTM support ended in April 2009).
Note that these dates are identical for Windows Server 2008 R2.
Mainstream support ends: No longer supported
Extended support ends: January 14, 2020
Taken from google, judge for yourself.