Day and Night World Clock
See local times around the world, according to Coordinated Universal Time. Understand the position of the Sun and the lengths of day and night across the year. Local time zone is automatically determined by the system clock time zone. Click "get local time" to retrieve current system time, and compute UTC accordingly.
The blue dashed line indicates the local time zone. Use the "local DST" checkbox if your local area observes Daylight Saving Time on a particular day of the year. Since it varies by country, Daylight Saving Time will not be set automatically.
"Day and Night World Clock"
Wolfram Demonstrations Project
Published: September 28 2007