MultiKit

Server Time Check: Accurate Clock to the Millisecond, and a Countdown

  • Free
  • No sign-up
  • Runs in your browser
  • Version 1.0.1
  • Last updated 2026-10-25
Report a problem

Check how far your device's clock is from a server's, and get a clock that shows the server's time to the millisecond. A countdown to a set time follows that clock, which is useful for a sale or a sign-up that opens at an exact moment.

Server time

--:--:--.---

Your device's clock

--:--:--.---

This is the time of MultiKit's own server, which is kept accurate, and how far your device's clock is from it. A browser cannot read the clock of another website's server, so this page cannot show that.

Count down to a time

For a sale, a ticket or a sign-up that opens at a set time. The count follows the server's clock, not your device's.

Everything you enter is processed in your browser and is never sent to a server.

Browsers:Chrome99+Edge99+Firefox93+Safari15.4+Opera85+Samsung Internet18.0+Browsers

How to use

  1. Open the page. It asks the server for the time several times, and the result appears in a few seconds: how many milliseconds your clock is fast or slow, and how sure the check is.
  2. The large clock shows the server's time, with milliseconds, in the time zone you choose. Below it is your device's own clock for comparison.
  3. To count down to a time, enter it, such as 20:00:00, choose the time zone it is in, and press Start. The count follows the server's clock, not your device's. Tick Beep to hear a sound when the time comes.
  4. Press Check again to repeat the check. The page also repeats it every few minutes, because a device's clock drifts.

Examples

Your clock is 0.8 s slow
→ The page says: Your clock is 800 ms slow, within ±30 ms
A phone or computer that has not synchronized its clock for a while can be off by a second or more.
Countdown to 20:00:00 in Seoul time
→ 1:02:03.4 left, and Now! at the moment the server's clock reads 20:00:00
The count runs by the server's clock, so it does not depend on whether your own clock is right.
Time zone UTC and Asia/Seoul
→ The same moment, 9 hours apart
Korea has no daylight saving time, so the difference stays at 9 hours all year.

How it works

The page sends a small request to MultiKit’s server, with a random number added to the address so that nothing comes from a cache, and notes when it left and when the reply arrived, using the browser’s high-resolution clock. The reply’s Date header gives the server’s time in whole seconds. If the server wrote the reply halfway through the round trip, its clock at that moment was somewhere from the Date value to one second after it, give or take half the round trip. That puts the server’s offset from your device in a range one second wide.

One range is not much, but the ranges of replies sent at different moments overlap in a narrower stretch, because a reply at the start of a second and one at the end do not allow the same offsets. The page asks up to 24 times, at uneven intervals, keeps the replies with the shortest round trips, and takes the middle of the overlap. When the overlap is smaller than 40 milliseconds it stops. If the replies disagree, for example because one was very slow, it takes the middle of them and says the answer is less sure.

The displayed time is your device’s high-resolution clock plus that offset, redrawn on every frame, and the countdown target is worked out in the time zone you choose, taking changes of daylight saving time into account. The logic is tested with simulated clocks and delays, with the time zone calculations, and in a browser against the real server reply.

This page shows the time of MultiKit’s own server only. It does not read other sites’ clocks, which browsers do not allow.

Sources

Frequently asked questions

How does a web page know the server's time?
Every reply from a web server carries a Date header with the server's clock. The page asks for a tiny reply several times and reads that header. The header is in whole seconds, so each reply only says the time was somewhere within a second; replies that arrive at different moments of the second rule out different parts of it, and together they narrow the answer to a few tens of milliseconds.
How accurate is it?
The page shows the accuracy of each check, as ± milliseconds, from the replies it received. Over a good connection it is typically within a few tens of milliseconds. A slow or unsteady connection makes it wider, and the page says so.
Can I see the server time of another website, such as a ticket site?
No. A browser does not let a web page read the clock in the replies of another site's server, so this page can only show the time of MultiKit's own server, which is kept accurate. Use it to check your own clock and as a reference to count down by. Another site's server may differ from it by some milliseconds or more.
Why is my device's clock off?
Clocks drift, and a device that has been off, has a weak battery or has automatic time turned off can be seconds out. Turning on automatic time in your system settings keeps it close. This page does not change your clock.
Will this help me get tickets or sign up first?
It shows the time and counts down to it, nothing more. It cannot make a site faster, and the site's own server decides when it opens. Do not rely on it for anything where a second matters.
What is sent to the server?
Only small requests for the page itself, as when you open any page, with a random number added to the address so the reply is fresh. Nothing you type, including the time you count down to, is sent.
Version history
  • 1.0.1 — Clarifies the search title with the tool's main task and whether it is free or runs online.
  • 1.0.0 — First release.

Last updated: