Free Online Digital Clock with Seconds
Loading the live clock. It is checked against server time.
What this online digital clock does
It shows the current time with seconds, in 12- or 24-hour format, in a light or dark theme, and full screen from the Display Mode control under the clock. Digital Clock Online checks your device clock against its server when the page loads and warns you if your device is wrong. Free, nothing to install, no account.
Seconds on or off
Show seconds when you are timing something, hide them for a calmer wall display.
12-hour or 24-hour
One tap switches the format. Your choice, and the seconds setting, are remembered on this device.
Full screen
The Fullscreen control fills your monitor with the clock. Press Esc or tap it again to leave.
Light and dark themes
Match the room. Dark for a desk at night, light for a projector or a bright classroom.
Checked against the server
If your device clock is off, you get a visible warning and a one-click fix.
Clocks for other places
247 countries and 312 time zones each have their own page with a live clock.
How the clock stays accurate
The clock you see runs on your device's own clock, which is what keeps the seconds smooth. What the site adds is a check. When the page loads, your browser asks the server for the time and compares it with your device, allowing for how long the request took.
If the two agree, nothing changes. If your device is noticeably off, a warning appears under the clock with the measured difference and a Sync button. Sync switches the display to server time for the rest of your visit.
Digital Clock Online does not claim atomic precision. Network latency limits any browser clock to roughly the round-trip time, typically well under a second. What you get is a clock that tells you when your computer is wrong, which is the failure that matters in an exam hall or a trading desk.
Compare your time with other places
Compare your local time with the places below. The live comparison loads with the page; add or remove places and they are remembered in this browser.
| Place | Time zone | Standard offset |
|---|---|---|
| United Kingdom · London | Europe/London | UTC+00:00 |
| United States · Washington D.C. | America/New_York | UTC-05:00 |
| France · Paris | Europe/Paris | UTC+01:00 |
Common uses
Classrooms and exam halls
Put the clock on the projector with seconds showing. Everyone in the room sees the same time, and the drift warning tells you if the classroom PC is off.
A second monitor at work
Keep a large clock on a spare screen while you are on calls with people in other zones. The comparison table below shows how far ahead or behind they are.
Travel planning
Open a country or time zone page for where you are going and compare it with your local clock before you book a call or a train.
How to use it
Show or hide seconds
Use the Visibility control under the clock.
Pick 12h or 24h
Use the Time Format control. The setting applies immediately.
Go full screen
Use the Display Mode control. Esc brings the page back.
Pick a theme
The sun and moon switch in the header toggles light and dark. The site starts dark.
Frequently asked questions
Is this clock accurate?
Can I make the clock full screen?
Do I need to install anything or sign up?
Can I show the time in another country?
Does it work on phones and tablets?
Why does the clock show dashes for a moment?
Other clocks on this site
Flip clock
A full-screen flip clock with the same controls, for a mechanical look.
Countdown timer
Set any duration and get an alert at zero. Stays accurate when you switch tabs.
Current time by country
247 countries and territories, each with its zones and daylight-saving rules.
Current time by timezone
312 IANA time zones with UTC offsets and a live clock for each.