Today, Windows users generally don’t have to worry about formatting their hard drive. Internal and external hard drives are formatted as they leave the factory and equipped with a specific file system, such as NTFS. In practice, however, there are situations in which formatting a hard drive can be useful or even necessary.
Formatting a hard drive: when is it necessary?
Typically, formatting a hard drive is necessary to commission a hard drive without a file system or when you plan to change the file system. For example, by switching from FAT32 to the NTFS file system, you will be able to save large files larger than 4 GB in size and enjoy increased security of your data.
Conversely, switching from NTFS to FAT32 can be useful if you want more mobility and better compatibility between platforms when exchanging data. A FAT32 hard drive can usually be read by local equipment such as media players or smart TVs. As Apple Mac computers can also handle FAT32 formatting of an external hard drive without additional tools, smooth data exchange between platforms is ensured.
A freshly formatted hard drive is also an ideal base for reinstalling a virus-free operating system and running smoothly. In addition, a complete reinstallation, including formatting the system hard drive, can be useful if you are upgrading, especially from Windows 7 to Windows 10.
For data security, formatting is only recommended to a limited extent. Under certain circumstances, a specific software can restore data that is invisible and unobtainable to an average user after formatting. If you want to sell a used hard drive that still contains sensitive data (eg confidential customer data and online banking information), you will need to employ specific removal tools. This software repeatedly overwrites data and adheres to mandatory security standards.
Windows offers built-in tools for formatting internal and external hard drives. We explain the different steps here using the example of Windows 10, but the procedure is very similar in Windows 7 and 8. Do you want to learn about the most common file systems for formatting data media? In our File System Overview, you’ll find out everything you need to know about the topic.
Quick format or full format: which to choose?
Whatever storage medium you buy, for internal or removable use, its manufacturer has already initialized it by a so-called “low-level” formatting operation, independent of the file system chosen afterward. So you don’t have to worry about this preparatory step.
The manufacturer has also prepared its support by a so-called “logical” (or “high level”) formatting, to create a file system, for example, FAT32, which makes the support immediately usable on many devices. But you can perfectly reformat a hard drive, memory card, or USB flash drive, either by choosing a different file system or by reinstalling the same file system on it to reset it in seconds. Because formatting causes you to lose all the data on the media. It is therefore important to check which medium you are formatting!
To be exact, in Windows as with all operating systems, a quick format just resets the disk index to zero and indicates that all space is now available. But files are often still recoverable by file recovery software (as long as the freed space is not taken up by a new file). Not all of them, but some nonetheless. If you are going to sell or give away a computer or external drive that has stored sensitive data, you may want to go beyond a quick format…
It’s planned. Windows offers you the possibility of carrying out formatting which certainly takes longer, but which will delete the contents of each sector of the disk, and mark bad blocks in passing to prevent them from being used in the future. File recovery is still sometimes possible by an expert, but much less obvious.
Which file system to choose for formatting?
Since we’ve said that choosing a file system is important when formatting, let’s take a look at the peculiarities of the ones you’ll come across most often.
FAT: You may have old small USB drives and low-capacity memory cards, up to 2 GB. They are often formatted in FAT. Beyond 2 GB, FAT32 and exFAT have taken over.
FAT32: Although aging, it is the most universal format, especially for removable media. It can be read and written by PCs, Macs, Linux, digital cameras, TVs, game consoles, Internet boxes, smartphones. Main restrictions: a file cannot exceed 4 GB, which is restrictive to create or play large videos in high definition, and the partition on the disk cannot exceed 2 TB. Prefer ExFAT when possible.
NTFS: Microsoft’s favorite format for PCs. Choose this format for the internal disks of your PCs running Windows 7, 8 or 10. But only adopt NTFS on your small external USB disks and other removable media if you are sure you only plug them into PCs running Windows (or Linux). On a Mac, for example, only reading NTFS partitions is allowed, not writing (at least not without adding special apps). And removable NTFS storages are not always read by TVs, consoles, and multimedia devices.
ExFAT: at the instigation of Microsoft, this format is intended to replace FAT32, the limits of which it removes. It was designed for removable storage like USB drives and small memory cards. It can be read and written by Windows, macOS, and Linux, and is also recognized and properly handled by newer media devices, like the Playstation 4 and Xbox One (but not the PS3 or Xbox 360, for example). Older devices don’t always recognize it. If a device supports both formats, prefer exFAT formatting rather than FAT32.
APFS and HFS +: Apple File System (APFS) is the latest evolution of Apple’s file system. Designed in particular to manage SSD disks more efficiently, it equips the latest versions of macOS, iOS, and tvOS (Apple TV), and succeeds the HFS + file system. These file systems are best used with macOS, on Mac internal drives, and USB external drives that you will only use on Macs, for automatic backups, for example. These formats not readable by Windows (without the addition of paid software) are rarely recognized by consumer electronics devices.
Ext2, ext3, ext4: the main GNU / Linux filesystems, not immediately recognized by Windows and macOS. Linux ext2 / 3/4 partitions are however accessible in read or read/write by installing free or paid software for Windows or macOS.
Note that Windows does not allow you to format the hard drive on which it is installed – which seems logical … But you can in particular reset this drive by requesting a restore of the PC to factory state (Windows keeps in a hidden partition of the hard disk the files necessary for its reinstallation).
Formatting in Windows File Explorer
When you do the formatting, you lose all your data. They will then no longer be accessible!
Process of formatting in Windows file explorer
After opening Windows File Manager with the key combination [Windows] + [E], you need to do the following steps:
- In the navigation menu to the left of the manager, click on the entry “This PC”.
- Once the available hard drives are listed, right-click on the icon of the drive to format.
- After opening the context menu, right click on “Format”.
- Configure the file system and start formatting by clicking on “Start”.
By default, Windows activates “Quick format”, which recreates the filesystem. If you uncheck this box, Windows will perform further formatting. The hard drive is then scanned for bad sectors, a step especially recommended for old or unused hardware. Also, in normal formatting, the partition is overwritten with zeros, which further complicates data recovery.
Formatting in Disk Management
The Disk Management is a Windows system tool including formatting and partitioning hard drives. To open it, do the following:
- Press the key combination [Windows] + [R].
- Enter “diskmgmt.msc”.
- Click on “OK”.
Open Windows Disk Management
Windows 10 users can also access Disk Management through the Windows symbol located at the bottom left of the taskbar. Right-click on the Windows symbol to open the menu and click on the “Disk Management” entry:
Access Disk Management via the Windows 10 taskbar
Disk Management opens after reading the connected hard disks:
Process of formatting a hard drive in Windows Disk Management
Follow these steps to format a hard drive in Disk Management:
- Right-click on the desired disk.
- Click on “Format”.
- Select the file system then click “OK”.
In step 3, you can again decide whether you want to perform quick format (box checked) or normal format with deleting and overwriting data (box unchecked).
Formatting a system hard drive
Formatting a fixed internal system drive is a special case and should be done differently. With this procedure, you can make unformatted or already formatted hard drives bootable, provide them with a new file system, and then install the desired operating system on them.
To do this, you will need specific installation media such as a Windows DVD or a bootable Windows USB stick. Formatting also works with the Windows Media Creation Tool, which allows you to create installation media for Windows 10. The actual formatting is done in a very similar way, regardless of the installation medium.
Formatting a system hard drive in Windows (7, 8, and 10)
Formatting of a system hard drive takes place during the startup phase. The boot sequence in BIOS must therefore be set so that the installation media is addressed first during booting and the PC boots from it. If these conditions are met, the formatting is then carried out in several steps:
If the installation media is active, it first guides you through several intermediate steps (eg entering a Windows license key, accepting the license terms, etc.). Windows installation then launches an installation and formatting wizard. In the menu “Choose an installation type”, you must click on the option “User-defined: install only Windows”:
“User-defined installation” with formatting options
Another window opens. If the hard drive has not yet been used and if it has not been formatted beforehand, you must proceed with a basic partition via “New”:
Partitioning and Allocating Disk Space in Windows Setup
If formatting has already been done and partitions are already displayed, you can click directly on the “Format” entry:
List of hard drives available in Windows installation
When creating a system disk, Windows always reserves disk space (“Disk 0 partition 1, type: system”), which is not accessible to users. The user-defined formatting is performed in the part marked in blue “Disk 0 partition 2, type: primary”).
If the system has more than one hard drive, you must make a choice. The system hard disk is usually “Data medium 0” or “Disk 0”. Formatting begins after validating a final security request. Once the process is complete, you can simply turn off or restart the computer (eg by pressing the Reset button).