How do I completely wipe and format a flash drive?

Formatting a flash drive is a quick and simple way to wipe all data so it cannot be recovered, while also preparing the drive for reuse. There are a few different methods you can use to format a flash drive, depending on your operating system and specific needs.

Why Would You Want to Format a Flash Drive?

Here are some common reasons for formatting a flash drive:

Wiping sensitive data before selling or gifting the drive

Removing malware or viruses
Fixing corruption errors or other issues
Preparing the drive for a new operating system

Restoring full storage capacity on the disk

Formatting overwrites all existing data on a drive. This data cannot be recovered without specialized tools. So formatting is an easy way to permanently wipe drives of all contents before disposing of, selling or repurposing the drive.

How Does Formatting Work?

When you format a drive, the operating system erases all existing file tables, partitions, and other structures on the disk. It then tests for bad sectors, creates a new master file table and root directory, and establishes a default file system structure for future storage use.

The actual data contents are not erased immediately when formatting a drive. The OS simply marks all previously allocated space as available for new data. This old data still physically exists on the drive until it gets overwritten gradually by new files saved after formatting.

For a quick wipe, you can overwrite all data manually by saving non-sensitive files to fill the disk after formatting. Or use a secure delete tool to overwrite all disk space with random data patterns.

Should You Do a Quick or Full Format?

Windows and other OS give you the choice between a quick or full format when erasing a drive. Here’s the difference:

Quick Format: This only empties the file tables and updates the file system. It does not scan for or erase bad sectors. Use this when you are formatting a new or recently formatted drive that does not need deep error checking.
Full Format: This scans the entire drive for bad sectors, including slow unreadable sectors. It erases all file tables, checks for physical errors on the disk, and prepares it for efficient storage use. Use this occasionally to thoroughly check and optimize a drive’s health.

In most cases, a quick format is sufficient for wiping previously stored data. Use the full format option occasionally for thorough drive maintenance.

How to Format a Flash Drive on Windows

Here is how to quickly format any flash drive, memory card or external storage device on a Windows PC:

Insert the flash drive into your computer.
Open File Explorer and click on the drive letter for your flash drive.

Right-click on the flash drive’s icon or drive letter and select Format.
In the Format window, choose the file system you want. FAT32 is best for compatibility.
Check the Quick Format box.

Click Start to begin formatting.

This process completely erases all data on the drive by overwriting the file tables. To permanently erase the actual data, use a secure delete program after formatting.

Alternative Wipe and Format Methods

Here are a few other ways to format a flash drive on Windows:

Use the diskpart command line utility. Open a Command Prompt window and type:

diskpart
list disk
select disk # (enter your flash drive number)  
clean
create partition primary
format fs=fat32 quick

Use Windows Explorer to format – right-click the drive, select “Format…” and adjust the settings
Use the Windows key + R to open the Run dialog, type “diskmgmt.msc” and press Enter, then select your flash drive and format.

How to Securely Wipe a Drive in Windows

If you need to permanently destroy all data on a flash drive before disposal, use a dedicated secure erase tool after formatting. Here are some options:

Sdelete – Free secure delete tool from Microsoft sysinternals. It overwrites all disk space for secure data destruction.
Eraser – Open source secure data wiping utility for Windows. It overwrites all unused disk space repeatedly.

Secure Erase – Hard drive utility built into Windows that completely erases data by overwriting it using security algorithms.

These tools use multiple rewrite passes with different data patterns to fully erase old contents beyond any hope of recovery. Use them after a standard format for added data security.

How to Format a Flash Drive on Mac

Here are the steps to quickly format a flash drive, SD card or external drive on MacOS:

Connect the external storage drive to your Mac.
Open Finder and click on the drive name in the lefthand sidebar.
Click Erase at the top of the window.

Give the drive a name and leave the default format as MS-DOS (FAT).
Click Erase to format the drive.

This will completely wipe the drive by overwriting the file tables and erasing all directory entries. To securely erase actual file contents, use a dedicated drive wipe utility after formatting on Mac.

Alternative Format Methods on Mac

Here are some other ways to format drives on MacOS:

Use Disk Utility – Select drive, click Erase button, and choose format.

Use diskutil in Terminal – run

diskutil eraseDisk FAT32 DRIVE_NAME DISK_IDENTIFIER

Use newfs_msdos in Terminal – run
```
newfs_msdos -F 32 /dev/diskX
```
to format in FAT32.

Securely Erasing Drives on Mac

To securely wipe all data from a drive on Mac:

Open Disk Utility and select the external drive.
Click Erase and choose a Secure Erase option like the 35-pass or 7-pass erase.
Click Erase to wipe the drive which may take hours.

You can also use third-party tools like Permanent Eraser, Secure Erase Mac, or ShredIt X to securely erase flash drives beyond recovery on Mac.

How to Format a Flash Drive on Linux

It’s easy to quickly format any external storage drive on a Linux distribution like Ubuntu. Here’s how:

Open the Terminal app and identify your flash drive with
```
lsblk
```

Unmount the flash drive partition, like
```
umount /dev/sdb1
```
(change sdb1 to your drive)
Format the drive with
```
mkfs.vfat -F 32 /dev/sdb1
```
(use your drive instead of sdb1)

This will format the flash drive in FAT32 format, erasing all file system information. To securely wipe all data from the drive, use shred or dd wipe utilities.

GUI Formatting on Linux

Most Linux desktop environments also let you format drives using a GUI:

GNOME Disks – Select drive, click hamburger menu icon, click Format Disk button
GParted – Right-click on drive, select Format to, choose file system
KDE Partition Manager – Select drive, go to Actions > Format Partition

Securely Wiping Drives on Linux

For secure data destruction on a flash drive or HDD on Linux, use:

Shred – Overwrite command to repeatedly erase files and disks.
Srm – Secure Recursive Wipe Command.

Dwipe – Drive Wiping Utility.
Bcwipe – Block Device Wiping Utility.
Dd – Data Duplicator – can erase disk with
```
dd if=/dev/zero of=/dev/sdX
```

Using these commands or a dedicated disk wipe tool is the most thorough way to permanently destroy all data on a drive before disposal.

How to Check if a Flash Drive is Fully Formatted

To verify formatting worked on a flash drive on Windows, Mac or Linux, check that:

All previous files and folders on the drive are now inaccessible or deleted

The drive’s storage capacity is reset to its full size
The operating system sees the filesystem as FAT32, exFAT, etc. depending on how you formatted it
You can now copy files to the drive and use it for storage

If you formatted the drive using a disk wipe utility, check the logs to confirm multiple erase passes were completed successfully.

Tips for Formatting Flash Drives

Follow these tips when formatting any flash drive, pen drive, or external storage device:

Always safely eject the drive first before formatting if currently connected to a PC.

Back up any important files before formatting as the process erases everything.
Use FAT32 for wide compatibility across OS, or exFAT for large drives over 32GB.
Quick Format is fine in most cases, use Full format periodically for drive maintenance.

For donating/selling drives, use a secure wipe tool or physical destruction for total data erasure.

Frequently Asked Questions

Is formatting the same as deleting everything on a flash drive?

Yes, formatting a flash drive will delete all data on the drive beyond basic recovery. Formatting overwrites the file system structures, erasing file tables, directory entries and markers that point to stored data on a drive. The actual raw data still remains until overwritten, so use a secure erase tool for total data destruction.

Can you recover data from a formatted flash drive?

In most cases, no. When you quickly format a flash drive, the file system is reset, but your existing data may still exist in raw form until it gets gradually overwritten by new data. However, recovering this raw data is extremely difficult without advanced forensic data recovery skills and tools.

Do I need to format a new flash drive?

You don’t need to format a brand new flash drive, but you may want to format it before first use for added security. When a drive is formatted by the manufacturer, it may have artifacts, test files or non-critical data left over from the QA testing process. Formatting it deletes these leftovers.

How long does it take to format a 128GB flash drive?

It typically only takes 1-2 minutes to full format a 128GB flash drive, depending on computer speed. Larger hard disk drives can take much longer, but flash storage can be formatted very quickly with solid state technology.

What is the best file system for USB flash drive – exFAT or FAT32?

FAT32 is best for maximum compatibility across all devices. However, it has a 4GB per-file size limit. exFAT removes this limit while still being widely compatible. So for very large flash drive capacities, exFAT is a better modern file system.

Conclusion

Formatting a flash drive is a quick and simple process to wipe all data and prepare it for reuse. On Windows, Mac and Linux, you can use built-in tools for a quick format to reset the drive. For maximum drive wiping security, use a secure delete utility after formatting to overwrite all old data.

With the steps provided above, you can easily format any flash drive, memory card or external storage device. Just remember to back up important files first before formatting a used drive, and use a thorough secure erase technique when disposing of sensitive drives.