Windows Calendar

Windows Calendar is the default calendar app in Windows Vista, Windows 8/8.1, Windows 10 and Windows 11.

16-bit Windows
Windows Calendar is included in Windows versions 1.0 to 3.11. It has been replaced in both Windows for Workgroups 3.1 with Schedule+, which is also included in Windows NT 3.x.

Windows 95
Windows 95 and Windows NT 4.0 do not ship with a calendar application and this continues all the way up to Windows XP, while Schedule+ has been shifted to Office 95 and turned into a 32-bit application.

Windows Vista
Windows Calendar on Vista supports sharing, subscribing, and publishing of calendars on WebDAV-enabled web servers and network shares. It supports .ics files, and the subscription feature enables syncing with Google Calendar. Its interface matches Windows Vista Mail. The default calendar can be renamed.

On the calendar taskbar applet, there is a date grid on the left side and a skeuomorphic analogue clock and a digital clock underneath on the right side. Additional clocks displaying different time zones can be added to the view. On the date grid (left side), dates far in the past or future can be looked up by zooming out by clicking on the date range indicator above the calendar grid, until each tile is a decade (e.g. 2010-2019, 2020-2029)

Windows 7
Although Windows Calendar was removed from Windows 7 in favor of the built-in calendar functionality in Windows Live Mail, it can be added back to Windows 7 by copying the program files from Windows Vista.

Windows 8
Windows Calendar was brought back in Windows 8/8.1, but in Metro language form.

Windows 10
The Calendar app from the original release had some changes, but mostly follows the same Metro language design as its 8/8.1 counterpart. A later update (2017 or 2018) replaced Metro with the Fluent Design language.