UFormat Date Formatting

Notes

By default, the date-time is displayed in long-date and long-time formats for the system locale.

When you pipe a date to cmdlets that expect string input, such as the Add-Content cmdlet, Windows PowerShell converts the DateTime object to a string before adding it to the file. The default ToString() format is short date and long time. To specify an alternate format, use the -Format or -UFormat parameters of Get-Date.
Here are the valid UFormat specifiers, each of which must be preceded by %, for example, Get-Date -UFormat %Y%m%d

Format specifier	Meaning	Example
A	Day of the week - full name	Monday
a	Day of the week - abbreviated name	Mon
B	Month name - full	January
b	Month name - abbreviated	Jan
C	Century	20 for 2006
c	Date and time - abbreviated	Fri Jun 16 10:31:27 2006
D	Date in mm/dd/yy format	06/14/06
d	Day of the month - 2 digits	05
e	Day of the month - digit preceded by a space	<space>5
G	Same as 'Y'
g	Same as 'y'
H	Hour in 24-hour format	17
h	Same as 'b'
I	Hour in 12 hour format	05
j	Day of the year	1-366
k	Same as 'H'
l	Same as 'I' (Upper-case I)	05
M	Minutes	35
m	Month number	06
n	newline character
p	AM or PM
R	Time in 24-hour format -no seconds	17:45
r	Time in 12-hour format	09:15:36 AM
S	Seconds	05
s	Seconds elapsed since January 1, 1970 00:00:00	1150451174.95705
t	Horizontal tab character
T	Time in 24 hour format	17:45:52
U	Same as 'W'
u	Day of the week - number	Monday = 1
V	Week of the year	01-53
w	Same as 'u'
W	Week of the year	00-52
X	Same as 'T'
x	Date in standard format for locale	09/12/07 for English-US
Y	Year in 4-digit format	2006
y	Year in 2-digit format	06
Z	Time zone offset from Universal Time Coordinate (UTC)	-07