Where to find the time settings on Windows and Mac

On a Windows computer, the fastest way is to click the time in the bottom right corner of your screen. A small window will pop up showing the date and time. Click "Change date and time settings" at the bottom of that window. This opens the Settings app directly to the Date & Time page, where you can adjust both the time and date.

On a Mac, click the clock in the top right corner of your menu bar, then click "Date & Time Preferences" at the bottom of the dropdown. This opens System Settings to the Date & Time section. Both paths take about 10 seconds.

If you cannot see the time on your screen, or if clicking it does nothing, your computer may have a permissions issue or a display problem. In that case, use the Settings app directly: on Windows, press the Windows key and type "date time" to search for it; on Mac, open System Settings and search for "date time" in the search box at the top.

Key Takeaways

  • Click the time in your system tray (Windows) or menu bar (Mac) to open date and time settings in seconds.
  • Turn off "Set time automatically" if you want to change the time manually, then type in the correct time and date.
  • If your computer keeps changing the time back, it is syncing with an internet time server — turn off automatic sync to keep your manual setting.
  • Changing the time on your computer does not affect other devices or accounts; each device keeps its own clock.

Turning off automatic time sync so your change stays

Most computers are set to update the time automatically from the internet. If you change the time manually and it reverts a few seconds later, this automatic sync is the reason. To keep your manual change, you need to turn it off first.

On Windows, in the Date & Time settings page, look for a toggle labeled "Set time automatically" near the top. Click it to turn it off. Once it is off, the time fields below will become editable — you can now click on the hour, minute, or second and type in the correct value. After you change it, click outside the field or press Enter to save.

On Mac, in Date & Time Preferences, uncheck the box next to "Set date and time automatically." The time and date fields will unlock. Click on the time field and type the new time in the format shown (usually HH:MM:SS). Click the date field to change the date using the calendar picker that appears.

When and why your computer time drifts

Computer clocks are not perfectly accurate. Over days or weeks, they can drift by a few minutes, especially on older machines or laptops that spend time in sleep mode. This is why automatic time sync exists — it corrects the drift by checking an internet time server (usually run by the National Institute of Standards and Technology, or NIST) every so often.

If you turn off automatic sync and notice your time drifting, you have two choices: turn automatic sync back on and let the computer correct itself, or manually adjust the time again when you notice it is wrong. For most people, leaving automatic sync on is simpler. You only need to turn it off if you have a specific reason — for example, if you are testing software that depends on a particular date, or if you are in a location without reliable internet and want to set the time once and leave it.

Changing the time zone on your computer

Your computer stores both a time and a time zone. If you travel or move, you may need to change the time zone so your computer displays the correct local time. This is separate from changing the actual time.

On Windows, in the Date & Time settings, scroll down to find "Time zone" and click the dropdown. Select your new time zone from the list. Windows will automatically adjust the displayed time to match. You do not need to turn off automatic sync to change the time zone.

On Mac, in Date & Time Preferences, click the lock icon in the bottom left to unlock the settings (you may need to enter your password). Then click "Time Zone" and type the name of your city or region. The system will find and explore the correct time zone automatically.

What happens if your computer time is very wrong

If your computer time is off by hours or days, a few things may not work correctly. Websites may refuse to load or show security warnings because the time mismatch makes the site's security certificate look invalid. Email may not send or receive. Some programs may refuse to open. These problems usually disappear as soon as you correct the time.

If you cannot remember the correct time, check your phone, a clock on the wall, or a website like time.gov (which displays the official U.S. time). Once you set the time correctly and turn automatic sync back on, your computer will stay accurate going forward.

Syncing time across multiple devices

Changing the time on your computer does not affect your phone, tablet, or other devices. Each device keeps its own clock and syncs independently with internet time servers. If you want all your devices to show the same time, they all need to have automatic time sync turned on, or you need to manually set each one.

If you use cloud services like OneDrive, Google Drive, or iCloud, the time on your computer does affect how those services work. File timestamps are based on your computer's clock, so if the time is wrong, files may appear to have been modified at strange times. Turning automatic sync back on will fix this.

Frequently Asked Questions

Why does my computer keep changing the time back after I set it?

Your computer is syncing with an internet time server. Go to Date & Time settings and turn off "Set time automatically" (Windows) or uncheck "Set date and time automatically" (Mac). Your manual change will then stay in place.

Can I change the time on my work computer?

That depends on your workplace's security settings. Many organizations lock the time settings so employees cannot change them. If the settings are grayed out or locked, contact your IT department — they may need to unlock them for you or change the time on your behalf.

Does changing my computer time affect my passwords or accounts?

Changing the time itself does not break passwords. However, if the time is very wrong, some security features may not work correctly — for example, two-factor authentication codes may be rejected if they are time-sensitive and your clock is far off. Correcting the time fixes this.

What is the difference between changing the time and changing the time zone?

The time zone tells your computer which region you are in; the time is the actual hour and minute. Changing the time zone automatically adjusts the displayed time. Changing the time manually overrides both. For most people, changing the time zone is the right choice when traveling.

Will changing the computer time affect my files or documents?

Files keep their original timestamps based on when they were created or last modified. Changing the computer time does not alter those timestamps retroactively. However, new files created after you change the time will have timestamps based on the new (incorrect) time, which can cause confusion.