Where to find the time settings on Windows and Mac

On Windows, right-click the clock in the bottom-right corner of your screen and select Adjust date and time. This opens the Settings app directly to the time controls. On Mac, click the Apple menu in the top-left, select System Settings, then click General in the sidebar and choose Date & Time.

Both operating systems let you toggle automatic time updates on or off. When automatic time is enabled, your computer syncs with internet time servers and adjusts for daylight saving time without you doing anything. This is the default on most computers and the easiest option for most people.

Key Takeaways

  • Windows users right-click the system clock and select Adjust date and time; Mac users go to System Settings > General > Date & Time.
  • Turning on automatic time keeps your clock accurate without manual updates and prevents security issues caused by incorrect system time.
  • If you need to set time manually, Windows and Mac both require you to disable automatic time first.
  • Your time zone setting affects when scheduled tasks run and how your computer displays times in emails and file timestamps.
  • Changing the system time can interfere with security certificates and two-factor authentication, so avoid manual changes unless necessary.

Turning automatic time on and off

On Windows 11, open the time settings as described above. You will see a toggle labeled Set time automatically. When this is on (the default), Windows pulls the correct time from Microsoft's time servers every time you connect to the internet. Turn it off only if you have a specific reason to set the time manually.

On Mac, the same setting appears in Date & Time as Set date and time automatically. When enabled, your Mac uses Apple's time servers and your location to set both the time and the time zone. If you turn this off, you can type in the time and date manually, but you will need to update it yourself if the system clock drifts.

Leaving automatic time on protects your computer in ways you may not see. Many security features depend on an accurate system clock. If your time is wrong by more than a few minutes, SSL certificates (the padlock in your browser) may fail to validate, and two-factor authentication codes may not work.

Setting your time zone correctly

Your time zone is separate from the clock itself. Even with automatic time enabled, you need to tell your computer which time zone you are in so it displays the correct local time. On Windows, scroll down in the time settings to Time zone and click the dropdown. Type the name of your city or region — Windows will suggest matches as you type.

On Mac, the time zone setting is in the same Date & Time panel. Click the dropdown next to Time zone and search by city name. Both systems will automatically adjust for daylight saving time in your region once you set the zone correctly.

If you travel frequently or work across multiple time zones, you can add additional clocks to your system. On Windows, open the time settings and scroll to Additional clocks. On Mac, open the Clock app and click the plus button to add clocks for other cities. These show up in your system tray or menu bar without changing your primary time zone.

Manually setting the time (when you must)

If automatic time is off and you need to set the time manually, the process is straightforward but should be rare. On Windows, turn off Set time automatically, then click Change under the date and time display. A dialog box opens where you can type in the correct date and time. On Mac, turn off Set date and time automatically, then click the date and time fields to edit them directly.

After you set the time manually, turn automatic time back on as soon as possible. Leaving it off means your clock will slowly drift out of sync, and you risk the security problems mentioned above. Manual time changes should only happen if your internet connection is down and you need to set the clock for a specific reason — like ensuring a scheduled backup runs at the right moment.

Why your computer's time matters for security

An incorrect system clock can break security features without you realizing it. SSL certificates used by banks and email providers include an expiration date. If your computer's time is set to the future, the certificate appears expired and your browser will block the connection. If your time is set to the past, the certificate appears not yet valid, and the same block happens.

Two-factor authentication codes are time-sensitive. They expire after 30 seconds, and if your system clock is off by more than a minute or two, the code you enter will be rejected even though it looks valid. This can lock you out of accounts temporarily. Keeping automatic time enabled prevents both of these problems.

Checking if your time is correct

If you are unsure whether your computer's time is accurate, compare it to a reliable source. On Windows, visit time.nist.gov in your browser — the National Institute of Standards and Technology displays the official U.S. time. On Mac, you can do the same, or open the Clock app and compare your system time to the world clock display.

If your time is off by more than a few seconds, check whether automatic time is enabled. If it is on but your clock is still wrong, restart your computer — sometimes the time service needs to reconnect to update. If automatic time is off, turn it back on and wait a minute for the system to sync. If the problem persists after a restart, your internet connection may be unstable, or your system clock hardware may be failing.

Frequently Asked Questions

Will changing the time zone affect my files or emails?

Changing your time zone will not alter the actual times stored in files or emails — it only changes how your computer displays those times. Emails sent at 3 p.m. in your old time zone will still show the same moment in time, but your computer will display it as a different local time once you switch zones. File timestamps work the same way.

What happens if I set my computer's time to the future?

Setting your time too far in the future can break SSL certificates and prevent you from accessing find websites. It can also cause scheduled tasks to skip or run at unexpected times. Turn automatic time back on to fix it — your computer will resync to the correct time within a few minutes of connecting to the internet.

Can I have my computer show time in a different format?

Yes. On Windows, go to Settings > Time & language > Language & region, scroll down, and click Related settings > Additional date, time & regional settings. You can change between 12-hour and 24-hour format, and customize how the date appears. On Mac, open System Settings > General > Date & Time and use the dropdown menus to choose your preferred format.

Why does my computer's time keep drifting even with automatic time on?

If automatic time is on but your clock still drifts, your internet connection may be dropping frequently, preventing regular syncs. Restart your computer and check your network connection. If the problem continues, your system clock hardware may be aging — this is rare on modern computers but more common on older machines.