TimeZoneCalculator

It respects the daylight saving based on UTC.

Installation:

Unpack and upload it to the /wp-content/plugins/ directory.
Activate the plugin through the 'Plugins' menu in WordPress.

What is new in this release:

• Remember last used timezone in calculator
• Added support link
• Set 403 http-status code for unauthorized ajax-calls

What is new in version 3.30:

• Remember last used timezone in calculator
• Added support link
• Set 403 http-status code for unauthorized ajax-calls

What is new in version 3.21:

• Renamed settings-page sections
• Moved vendor-code to separate directory
• Fixed small potential bug
• Cleaned-up code
• Implemented minor design changes
• SSLified links
• Added assets/icons

What is new in version 2.44:

• Adopted 'Defaults'-string to use WordPress internal i18n.
• Updated support section.
• Updated project-information.

What is new in version 2.10:

• Added $params['user_id'] as argument of $timezonecalculator->output() to make it possible for users to access the timezones of other users.
• The access to the user's timezones-selection can be restricted.
• Reworked and extended a few internal functions.
• Corrected a few typos and fixed potential bugs.

Requirements:

• WordPress 3.3 or higher