Formatting a hard drive allows you to use it on your computer to save files and install programs. The format you choose for the disc will determine its compatibility. Formatting a disk will erase all current data, so make sure you have a backup. You can format a secondary disk directly from the operating system, or you can format the boot disk using your operating system's installation disk. If you need to delete data for security reasons, there are free tools that allow you to completely wipe a disk so that nothing can be recovered.
Steps
Method 1 of 5: Format a Secondary Hard Drive (Windows)
Step 1. Back up any data on the drive you don't want to lose
Formatting a disk will lose all data on it, so make sure any data you want to keep is saved in a safe location. You will be able to return them to the disk once it is formatted.
Installed programs cannot be backed up. You will need to reinstall them on the new disk. However, you can usually back up your settings and preferences files
Step 2. Install the new hard drive
If you are formatting a new disk, you will need to install it on your system. If the drive is external, you can connect it to your computer via USB.
Step 3. Open Computer
You can access it from the Start menu, or by pressing ⊞ Win + E. You will see all the disks connected to your computer.
Step 4. Right click on the drive you want to format
Select "Format …" The Windows Disk Format utility will open.
Make sure you choose the right drive. It will be cleared completion upon formatting
Step 5. Select the file system
The file system is the way in which the disk stores and catalogs files. The file system will determine the compatibility of the disk. If the disk is internal and you are using it for Windows computers only, choose NTFS. If the disk is external, choose FAT 32 or exFAT.
- These two formats can be read and written by all new operating systems. FAT32 is an older system, which does not support files larger than 4GB, but which can be read by virtually all operating systems. exFAT has no restrictions, but it won't work on older operating systems like Windows 95.
- In general, exFAT is the best option for external drives. It is compatible with most systems and allows the storage of large files.
Step 6. Give the disk a name
If you are using the disk for one use, giving it a name will help you understand what is inside it. For example, if you are using a secondary drive to store music, movies and pictures, you can name it "Media" to recognize at a glance what it contains.
Step 7. Choose whether or not to enable Quick Format
This option allows formatting to be done much faster than standard formatting, and is suitable for most users. Only perform a normal format if you suspect the disk may contain errors. Standard formatting may be able to correct some of these errors.
The Quick Format option does not affect the security degree of data deletion. If you need to securely delete all data, read the last section of the article
Step 8. Start formatting
Click Start to begin formatting. Click OK to confirm that you understand that all data will be deleted. If you have Quick Format selected, this should only take a few seconds.
Method 2 of 5: Format a Secondary Hard Drive (OS X)
Step 1. Back up any data on the drive you don't want to lose
Formatting a disk will lose all data on it, so make sure any data you want to keep is saved in a safe location. You will be able to return them to the disk once it is formatted.
Installed programs cannot be backed up. You will need to reinstall them on the new disk. However, you can usually back up your settings and preferences files
Step 2. Install the new hard drive
If you are formatting a new disk, you will need to install it on your system. If the drive is external, connect it to your computer via USB, FireWire, or Thunderbolt.
Step 3. Open Disk Utility
Click on Go and then on "Utilities". If you don't see "Utilities", select "Applications" and then double click on the "Utilities" folder. Open the Disk Utility program.
Step 4. Select the disk from the left list
All connected disks will be listed in the left panel of the Disk Utility window. Make sure you choose the right drive.
Step 5. Click on the "Delete" tab
The format options for the disk will open.
Step 6. Choose the file system
The file system is the way in which the disk stores and catalogs files. The file system will determine the compatibility of the disk. Use the Volume Format drop-down menu to choose it. If the disk is internal and you are using it only with OS X, choose "Mac OS Extended (Journaled)". If the drive is external, choose exFAT.
- FAT32 and exFAT can be read and written by all new operating systems. FAT32 is an older system, which does not support files larger than 4GB, but which can be read by virtually all operating systems. exFAT has no restrictions, but it won't work on older operating systems like Windows 95.
- In general, exFAT is the best option for external drives. It is compatible with most systems and allows the storage of large files.
Step 7. Name the drive
If you are using the disk for one use, giving it a name will help you understand what is inside it. For example, if you are using a secondary drive to store music, movies and pictures, you can name it "Media" to recognize at a glance what it contains.
Step 8. Start the format operation
Click Erase to start formatting the disk. The format operation should only take a few seconds.
Formatting the disk in this way does not allow you to securely delete the data. To do this, read the last section of the article
Method 3 of 5: Format Your Startup Disk (Windows)
Step 1. Back up any data on the drive you don't want to lose
Formatting the startup disk will erase the operating system and all files contained within it, so be prepared to reinstall the operating system on the disk. Creating a backup of your most important files will allow you to make this transition much easier.
Step 2. Insert the Windows installation disc
You can also use a startup disk or LiveCD. This way you can boot from CD and not hard drive, and format it.
Step 3. Set your computer to boot from the CD
You will need to change the boot order from the BIOS to be able to boot from CD.
To open your BIOS, restart your computer and press the setup button, usually F2, F10, or Del
Step 4. Navigate through the installation screens
You will have to start the installer and go through the first few pages, until you see the screen with the list of installed drivers. You will need to start a Custom Windows Installation.
Step 5. Choose the drive to format
You will see the list of all your disks and the partitions they contain. Choose the disk to format, then click the "Format" button below. The disk will be formatted as NTFS.
You can format the startup disk as NTFS only
Step 6. Reinstall Windows
Now that the drive has been formatted, you can reinstall Windows, or install Linux. You will need an operating system on your computer to use it.
Method 4 of 5: Format Your Startup Disk (OS X)
Step 1. Back up any data on the drive you don't want to lose
Formatting the startup disk will erase the operating system and all files contained within it, so be prepared to reinstall the operating system on the disk. Creating a backup of your most important files will allow you to make this transition much easier.
Installed programs cannot be backed up. You will need to reinstall them on the new disk. However, you can usually back up your settings and preferences files
Step 2. Make sure you are connected to the internet
You will need an internet connection to reinstall your operating system after the operation is complete.
Step 3. Restart your computer
Click on the Apple menu and select "Restart". Hold down ⌘ Command + R while the computer restarts. This will open the start menu.
Step 4. Select "Disk Utility" from the start menu
This will open the version of the Disk Utility program that you can view at startup.
Step 5. Select the disk from the left list
You will see all the disks in the left pane of the Disk Utility. Make sure you choose the right drive, because during formatting you will erase all the data there.
Step 6. Choose the file system
The file system is the way in which the disk stores and catalogs files. The file system will determine the compatibility of the disk. Since this is the startup disk, select "Mac OS Extended (Journaled)".
Step 7. Name the drive
For example, if you are formatting the disk to reinstall the operating system, name it "OS X" or something similar.
Step 8. Format the drive
Click Erase to format the disk. This should only take a few seconds.
Step 9. Close the Disk Utility
This will take you back to the start menu.
Step 10. Reinstall OS X
Select "Reinstall OS X" to begin reinstalling your operating system.
Method 5 of 5: Permanently Erase All Data from Your Hard Drive
Step 1. Back up any data on the drive you don't want to lose
When you permanently delete files from your hard drive, there is no way to get them back. It takes days and a government supercomputer to recover file fragments from a hard drive that has been successfully erased. For this, make sure you have saved everything you want to keep.
Step 2. Download DBAN
DBAN is a hard drive formatting program designed to permanently erase data from drives, overwriting them many times. This way the data cannot be recovered with a data recovery program.
DBAN does not work with solid state drives (SSDs). In this case you will have to use a different program, such as Blancco
Step 3. Write DBAN to disk
You can download DBAN as an ISO file, which is a disk image. Writing the ISO to a disk will allow you to boot directly into the DBAN interface.
Step 4. Boot your computer with the DBAN disk
Insert the DBAN disk into your computer and restart it. Choose the CD drive as the primary boot device.
- Windows - You will need to configure the optical drive as a boot drive from the BIOS menu.
- OS X - Press and hold C while the computer restarts. After a short time, DBAN will start.
Step 5. Choose the hard drive
Press Enter on the DBAN home screen, then choose your disk with the directional arrows. Make sure you choose the right disk if there is more than one on your computer.
Step 6. Choose the cancellation method
"DoD" will erase the data permanently, and is an erasing method suitable for most users. If there is very, very important information on the disc, choose the "8-Pass PRNG Stream" mode. Your disk will be overwritten eight times with randomly generated numbers, completely erasing your data.
Step 7. Start formatting
Once the cancellation mode has been chosen, the operation will begin. Erasing with DBAN can take many hours or days, depending on the size of the disk and how it is erased.
