This wikiHow teaches you how to divide your computer's hard drive into two parts (or "partitions"). By partitioning, you can treat your hard drive like two separate disks. This is especially useful when you want to install multiple operating systems on one computer. You can create partitions on your existing hard drive on a Windows or Mac computer.
Step
Method 1 of 2: On Windows Computer
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Step 1. Go to Start
Click the Windows logo in the lower left corner.
You can also press Win on your computer keyboard
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Step 2. Type computer management into Start
The computer will search for the Computer Management program.
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Step 3. Click Computer Management at the top of the Start window
Computer Management will open.
If you are not logged in as an administrator, you may not be able to access this program
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Step 4. Click Disk Management
This tab is located in the sidebar on the left side of the Computer Management window.
If this option is not present, double click Storage first.
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Step 5. Select the hard disk
In the window at the bottom of Computer Management, click your hard drive box. This box displays the hard drive letter (eg "(D:)") and the amount of usable storage capacity (in gigabytes or GB).
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Step 6. Click Actions
This tab is in the upper-left side of the Computer Management window. A drop-down menu will be displayed.
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Step 7. Select All Tasks
This option is at the bottom of the drop-down menu. A pop-out menu will be displayed.
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Step 8. Click Shrink Volume… in the middle of the pop-out menu
By clicking Shrink Volume…, Windows will determine the amount of free space available on the hard disk. A new window will be opened once this process is complete.
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Step 9. Set the partition size in megabytes
Type the desired number of megabytes for the partition into the "Enter the amount of space to shrink in MB" text field to the right of the page.
- The maximum number of megabytes that can be allocated will be displayed just above the column you entered the number in.
- One gigabyte (GB) is 1000 megabytes (MB). If you want to create a partition of 5 GB, you must type 5000 in the text field.
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Step 10. Click Shrink located at the bottom of the page
The computer will start creating segments of the hard disk that will serve as partitions.
The process may take a few minutes
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Step 11. Select the new partition
Click the new partition that says " Unallocated ", to the right of the hard disk space.
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Step 12. Click Action again
This tab is in the upper-left side of the window.
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Step 13. Select All Tasks, then click New Simple Volume….
This option is at the top of the pop-out window.
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Step 14. Click Next at the bottom right of the window
The screen for the initial partition setup will be displayed.
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Step 15. Click Next
Doing so will accept the partition size you specified, and the next page will be displayed.
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Step 16. Select a drive letter (drive), then click Next
The partition's drive letter (eg "E") can be changed by clicking the drop-down box, then clicking the new letter.
This step is optional
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Step 17. Check the box "Format this volume with the following settings"
The box is at the top of the page. This option will set the partition to Windows default settings, so it can be used on Windows like a normal hard disk.
- If the "File system" box doesn't say "NTFS", click the box, then click NTFS. The partition will be formatted with the file system for Windows.
- You can also rename the partition in the " Volume label " box.
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Step 18. Click Next at the bottom of the page
Next, the last page will be displayed.
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Step 19. Click Finish
Once you do that, the computer will start creating partitions on the drive. Once the process is complete, you can use the partition in the This PC program. The partition will appear next to the hard drive in the " Devices and drives " section.
The partitioning process can take a few minutes to several hours depending on the size of the hard disk and the size of the partition
Method 2 of 2: On Mac Computer
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Step 1. Click Go
This tab is in your Mac's menu bar at the top of the screen.
If Go nothing, bring up this tab by clicking on the desktop or opening a new Finder window.
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Step 2. Click Utilities
It's at the bottom of the drop-down menu Go.
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Step 3. Double-click Disk Utility
The icon is a Mac hard disk with a stethoscope on it. The Disk Utility program will open.
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Step 4. Select the hard disk
Click your Mac's hard drive in the upper-left side of the Disk Utility window, under the "Internal" heading.
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Step 5. Click Partition
This tab is located at the top of the Disk Utility window.
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Step 6. Click +
It's below the hard drive circle on the left side of the page.
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Step 7. Set the partition size
Click and drag the button at the bottom of the hard disk circle counterclockwise to increase the size of the partition, or clockwise to decrease it.
You can also enter a number in gigabytes (GB) in the " Size: " field to specify the partition size
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Step 8. Select the file format for the partition
Click the File Format drop-down box, and then select a format. The format you choose will be set as the file system on that partition.
- If you want to use the partition on a Mac computer, select the option MacOS Extended in the drop-down menu.
- You can also give the partition a name in the " Name: " field.
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Step 9. Click Apply in the lower right corner
The Mac computer will start creating partitions.
The process can take some time, especially if the hard drive and partitions are larger than one terabyte
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Step 10. Click Done when prompted
The partition for Mac computer has been created successfully.