A big, clear clock for any screen
Use it as a desk clock on a second monitor, a classroom clock on the projector, or a timekeeper on stage. Full screen hides everything except the time. The analog face and the seconds can be switched on or off.
The clock shows your device’s time. Phones and computers set it automatically from internet time servers, so it is normally correct to within a fraction of a second. For an official US reference, compare it with time.gov, which is run by NIST.
12-hour vs. 24-hour time
The US, Canada, the Philippines, India and Australia mostly speak and write in 12-hour time with AM and PM. The 24-hour format, often called “military time” in the US, is standard in the armed forces, hospitals, aviation and on most of the world’s timetables. The dial below puts both on one face.
| 24-hour | 12-hour | Said in military style |
|---|---|---|
| 00:00 | 12:00 AM (midnight) | “zero hundred” |
| 06:30 | 6:30 AM | “oh-six-thirty” |
| 12:00 | 12:00 PM (noon) | “twelve hundred” |
| 15:00 | 3:00 PM | “fifteen hundred” |
| 21:15 | 9:15 PM | “twenty-one fifteen” |
12 AM and 12 PM cause the most mix-ups. Noon is 12 PM; midnight is 12 AM and starts the new day. When it really matters (a contract deadline, a flight), write “12:00 noon” or “11:59 PM” instead.
Want the time somewhere else? Open the world clock.
Frequently asked questions
Is this clock accurate?
It is as accurate as your device clock, which syncs automatically with internet time servers. If it looks wrong, check your device’s date, time and time zone settings.
How do I switch to 24-hour time?
Open settings (gear icon) and choose 24-hour format. The choice is remembered.
Can I keep the screen from turning off?
Yes. In full screen the page asks supporting browsers to keep the display awake.
Is 12 AM midnight or noon?
Midnight. 12 PM is noon.
Every date, offset and calculation on this page was checked against the sources below.