Partitioning an SD card is useful for isolating sensitive or personal files, creating a backup drive for programs and operating system, or even improving the performance of your computer or mobile device. SD cards can be partitioned using a Windows computer, Mac or Android device.
Steps
Method 1 of 3: Windows
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Step 1. Insert the SD card into your computer's reader
If your computer doesn't have an SD card reader, you can purchase an external USB one.
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Step 2. Go to the "Start" menu and click on the "Control Panel" item
The Windows "Control Panel" window will appear.
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Step 3. Click on the "System and Security" category, then select the "Administrative Tools" link
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Step 4. Click on the "Computer Management" icon
The "Computer Management" system application window will appear.
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Step 5. Click on "Disk Management", located in the left pane of the window in the "Storage" section
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Step 6. Select the SD card name with the right mouse button, then choose the "New Simple Volume" option from the context menu that will appear
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Step 7. Click on the "Next" button displayed in the "New Simple Volume Wizard" window that appears on the screen
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Step 8. Type the size you want to set for the new partition, then click the "Next" button
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Step 9. Choose the drive letter that will be used to identify the new partition, then click the "Next" button
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Step 10. Choose whether you want the new partition to be formatted or not, then click the "Next" button
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Step 11. Click on the "Finish" button
At this point, the SD card has been partitioned successfully.
Method 2 of 3: Mac
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Step 1. Insert the SD card into your computer's reader
If your Mac doesn't have an SD card reader, you can buy an external USB one.
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Step 2. Open the "Applications" folder, then click on the "Utilities" directory
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Step 3. Click on the "Disk Utility" icon
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Step 4. Click on the SD card name listed in the left pane of the "Disk Utility" window
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Step 5. Click on the "Partition" tab displayed at the top of the "Disk Utility" window
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Step 6. Click on the "Volume Scheme" drop-down menu, then choose the number of partitions you want to create on the SD card
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Step 7. Click on each partition and name each of them, then choose the file system format and set a size
If you want to use the SD card as a startup disk, click the "Options" button, then choose the "GUID Partition Table" item
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Step 8. Click the Apply button"
At this point, the SD card has been successfully partitioned.
Method 3 of 3: Android devices
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Step 1. Verify that the SD card you want to partition is inserted into the Android device
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Step 2. Access the Google Play Store from your Android device
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Step 3. Search and download the ROM Manager app developed by ClockworkMod
Alternatively, you can install the ROM Manager app by visiting the website
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Step 4. Launch the ROM Manager app after the installation is complete
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Step 5. Select the "Partition SD Card" item
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Step 6. Choose the partition size using the "Ext Size" pop-up
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Step 7. Select a value from the "Swap Size" menu
This is the number of MB of the SD card that can be used as cache memory, in order to free up RAM for other programs and apps.
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Step 8. Press the "OK" button
Your Android device will restart in "Recovery" mode and the SD card will be partitioned.
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Step 9. Choose to restart the device when prompted
At this point, the SD card has been partitioned successfully.