Live city clocks, UTC offsets, and the solar day/night line
This map is live. City clocks show each city's official UTC offset. The shading is solar day and night — it is not a map of legal timezone borders.
Leave LIVE on for the current moment, or freeze the clock to inspect a specific UTC time.
A timezone name is not the same as the hours on the clock. Click a city to see its local time and UTC offset. To compare cities, open the time-difference list.
The map calculates the sun's position from your PC clock and draws the day/night boundary in real time. No server calls — works offline too.
By default the map runs in LIVE mode, updating every second. Set a specific date/time or use the URL ?time= parameter to freeze at any moment.
Click a city marker to see its current local time, calculated from UTC + the city's timezone offset. The popup updates in real time during LIVE mode.
When you set a specific time, the URL updates automatically. Copy and share the URL to show someone the exact same day/night view.
Use the Play button to animate the day/night boundary moving across the globe. Each step advances one minute, so you can watch a full day pass in seconds.
Visually check what time it is across multiple cities before scheduling a call or video conference across time zones.
See where it will be day or night when you arrive at your destination. Great for planning flights and adjusting to jet lag.
DevOps and support teams can see at a glance which offices or data centers are in business hours versus overnight.
Demonstrate how Earth's rotation and axial tilt create seasons and varying day lengths. Perfect for geography or astronomy classes.