What is NTP?
NTP stands for Network Time Protocol. It is the standard protocol computers use to keep clocks synchronized over a network.
System clock setup
Network Time Protocol (NTP) setup guide
Most personal devices should use their built-in automatic time setting. Start with the device clock guide; the Network Time Protocol (NTP) steps below are for servers, routers, network appliances, or custom time sources.
Start with the safest fix
Use automatic settings before setting the clock by hand. Manual correction can drift again and may leave the time zone wrong.
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Turn on automatic time
Open the device date and time settings and enable automatic time or network-provided time.
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Confirm the time zone
Enable automatic time zone, or select the correct city and region if automatic detection is unavailable.
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Sync, then check again
Use Sync now when your system provides it, wait a moment, and run the clock drift test again.
Verify after setup
After your system syncs, open the clock drift test. Use the measured clock offset and its error range to judge alignment; network latency describes the measurement conditions, not whether the clock is correct.
Run clock drift test- Check offset
- Run the clock drift test before and after changing settings so you can compare the result.
- Check service state
- Confirm the operating system reports network time as enabled and synchronized.
- Wait for resync
- Some systems sync on an interval, so the offset may improve a few minutes after setup.
Public NTP options
Keep the operating system, workplace, school, or ISP time source when it synchronizes successfully. Use a public provider only when you need a custom server.
- A regional NTP Pool zone can be a fallback, but confirm that the zone is available and well supplied.
- Google Public NTP uses leap smearing. Do not mix it with sources that use a different leap-second policy.
Before you change the server
A nearby server is not automatically more accurate. Prefer a source managed by your operating system or network, and change it only after the default source fails or an administrator requires another policy.
Check current sync status
Windows 11 · PowerShell (run as administrator)
w32tm /query /statusmacOS · Terminal check (sudo)
sudo systemsetup -getusingnetworktimesystemd-timesyncd
timedatectl statuschrony
chronyc trackingTroubleshooting
- Offset stays above one second
- Check automatic time, service state, and whether network port UDP 123, used by NTP, is blocked.
- Time zone looks wrong but offset is small
- NTP synchronizes absolute time. Change your operating system time zone separately.
- Virtual machines keep drifting
- Check both guest time service and host integration settings.
NTP FAQ
Which NTP server should I use?
Start with the source supplied by your operating system, workplace, school, or ISP. If you need a custom public source, compare NTP Pool, Cloudflare, and Google, follow the provider policy, and do not mix incompatible leap-second strategies.
Why does accurate system time matter?
Accurate system time helps authentication, secure website (HTTPS) certificates, logs, scheduled jobs, backups, and distributed systems work correctly.