Date and Time Options 
Path to Date and Time options: Settings > Options > Date and Time Options.

Date and Time formats in vBulletin follow standard PHP formatting rules. For more information see the PHP reference manual.
Note:
You must click Save for changes to take effect.


Datestamp Display Option (default: Yesterday / Today)

Controls the display of dates throughout the site.

'Normal' uses the date and time formats below this option.

'Yesterday / Today' shows 'Yesterday' and 'Today' for dates that fall in those periods.

'Detailed' shows times such as '1 Minute Ago', '1 Hour Ago', '1 Day Ago', and '1 Week Ago'.


Default Time Zone Offset

Time zone offset for guests and new users. When using this setting, do not take DST (Daylight Savings Time) into consideration; instead, use the Enable Daylight Savings option to enable or disable DST.


Enable Daylight Savings

If DST is currently in effect for the time zone, enable this option so guests see the correct times on posts and events. (This setting has no effect on registered users, because they control their DST options in the User Control Panel.)

This setting is not automatic and needs to be changed with the standard/daylight switch twice a year.


Format for Date (default: m-d-Y)

Format for dates shown on vBulletin pages.

Examples:
US Format (e.g., 04-25-98): m-d-y
Expanded US Format (e.g., April 25th, 1998): F jS, Y
European Format (e.g., 25-04-98): d-m-y
Expanded European Format (e.g., 25th April 1998): jS F Y


Format for Time (default: h:i A)

Format for times shown on vBulletin pages.

Examples:
AM/PM Time Format (eg, 11:15 PM): h:i A
24-Hour Format Time (eg, 23:15): H:i


Format for Registration Date (default: M Y)

The user registration date shown in the upper left-hand column of users’ posts.


Format for Birthdays with Year Specified (default: F j, Y)

Date format in cases where the birth year is specified in the user profile.


Format for Birthdays with Year Unspecified (default: F j)

Date format in cases where the birth year is unspecified in the user profile.


Log Date Format (default: H:i, jS M Y)

Format of dates shown in Control Panel logs.
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