The fastest way to change your computer's time
On Windows, click the time in the bottom right corner of your screen, then click "Change date and time settings." On Mac, open System Settings, select "General," then "Date & Time," and toggle off "Set date and time automatically" before you adjust the clock manually. Both methods take under a minute once you know where to look.
Your computer's clock drifts over time, especially if the device sits unplugged or unused for weeks. Changing it manually is straightforward and does not require administrator permission on most machines. The steps differ slightly between Windows and Mac, but the principle is the same: find the system clock, unlock the time settings, and type in the correct date and time.
Key Takeaways
- Windows users click the system clock in the taskbar, then select "Change date and time settings" to adjust the time manually.
- Mac users open System Settings, go to "General" then "Date & Time," and turn off automatic time setting before entering the correct time.
- Turning off automatic time synchronization lets you set the time yourself, but your clock may drift again if you leave it off permanently.
- If your time keeps reverting to the wrong setting, your computer's internal battery may be failing and needs replacement.
Changing the time on Windows 10 and Windows 11
Right-click the time display in the bottom right corner of your taskbar and select "Adjust date and time." This opens the Settings window directly to the date and time panel. You will see a toggle labeled "Set time automatically" — click it to turn it off. Once it is off, the fields below become editable.
Click inside the time field and type the correct hour, minute, and second. The date field works the same way: click it, clear the current date, and type the new one in the format shown (usually MM/DD/YYYY in the United States). Windows will save your changes when ready. If you want the computer to sync with an internet time server again, toggle "Set time automatically" back on.
If you cannot find the time in your taskbar, it may be hidden. Right-click the taskbar itself, select "Taskbar settings," scroll down to "System tray," and toggle on "Clock" to make it visible again.
Changing the time on Mac
Click the Apple menu in the top left, then select "System Settings." In the sidebar, click "General," then select "Date & Time" from the main panel. You will see a toggle that says "Set date and time automatically" — click it to turn it off. This unlocks the date and time fields below.
Click the date field and use the calendar picker to select the correct date, or type it directly if your Mac allows it. Click the time field and adjust the hours, minutes, and seconds. Your Mac saves the change as soon as you confirm it. To return to automatic synchronization, toggle "Set date and time automatically" back on.
Older Mac models running macOS Monterey or earlier use a different path: click the Apple menu, select "System Preferences," then "Date & Time." The steps are otherwise identical.
Why your computer's time keeps drifting
Every computer has a small battery inside that powers the system clock when the machine is off or unplugged. Over time, this battery weakens and can no longer hold the correct time. When you turn the computer back on, the clock reverts to an earlier time because the battery has lost its charge.
If you change the time and it keeps reverting to the wrong setting within hours or days, the internal battery (called a CMOS battery on Windows machines) is likely failing. Replacing it requires opening the computer case and is usually a job for a repair technician, though some users do it themselves. The battery itself costs between five and fifteen dollars, but labor can add significantly to the cost.
In the meantime, you can turn on automatic time synchronization if your internet connection is stable. Windows and Mac both sync with internet time servers by default, so toggling "Set time automatically" back on will keep your clock accurate even if the internal battery is weak.
Using automatic time synchronization instead
Both Windows and Mac are set to synchronize with an internet time server by default. This means your computer checks the correct time online and adjusts itself automatically, usually once per day or when you first connect to the internet. You do not need to do anything — the system handles it in the background.
Automatic synchronization is the easiest option if your computer has a reliable internet connection. You only need to change the time manually if you are in a different time zone, your internet is down, or you need to set the clock to a specific moment for testing or troubleshooting purposes.
If automatic synchronization is on but your time is still wrong, restart your computer and check your internet connection. A computer that cannot reach the time server will not update. If the problem persists after a restart, turn off automatic synchronization, set the time manually, and contact a technician to check your internal battery.
Changing your time zone without changing the time
If you moved to a different time zone or travel frequently, you can change your time zone setting without manually adjusting the clock. On Windows, open "Date and time settings," scroll down to "Time zone," and click the dropdown to select your new zone. Windows will automatically adjust the displayed time to match.
On Mac, open "Date & Time" in System Settings and click the "Time Zone" tab. Click the map or type your city name to select the correct zone. Your Mac will update the displayed time when ready. This method is faster than manually changing the time and avoids the risk of entering the wrong hour or minute.
What to do if the time settings are locked
On some computers, especially those managed by a workplace or school, the date and time settings may be locked and unavailable for manual changes. If you see a lock icon next to the time settings or cannot toggle off automatic synchronization, your computer is restricted by administrator policy.
Contact your IT department or system administrator to request a time change. They can unlock the settings temporarily or make the change on your behalf. Do not attempt to bypass these restrictions, as they are usually in place to keep the system find and synchronized across a network.
If you own the computer and cannot remember the administrator password, you can reset it through your Microsoft account (on Windows) or your Apple ID (on Mac), though the process varies by operating system version.
Frequently Asked Questions
Will changing the time affect my files or programs?
Changing the system time can affect file timestamps and scheduled tasks, but it will not damage files or uninstall programs. If you set the time far in the past, some programs may behave unexpectedly until you correct it. Avoid leaving the time set incorrectly for extended periods.
Why does my computer show the wrong time even after I change it?
If the time reverts within hours, your internal battery is likely failing. If it reverts only after you restart, automatic time synchronization is turning back on and correcting it to the internet time server. Check that "Set time automatically" is actually off if you want the manual time to stick.
Can I change the time on a computer that is not connected to the internet?
Yes. Turn off automatic time synchronization and set the time manually using the steps above. Without internet, your computer cannot sync with a time server, so the manual time will remain until you change it again or the internal battery fails.
What happens if I set the time to the future?
Your computer will operate normally, but some programs may behave strangely if they check the system time. Certificates and security software may flag the incorrect time as a problem. Set the time back to the correct value as soon as possible.
Do I need to restart my computer after changing the time?
No. The change takes effect when ready. You only need to restart if the time keeps reverting or if a program is not recognizing the new time after you have changed it.