Ways to format disk and delete everything from computer

On any computer we can find passwords, addresses, telephone numbers, access to bank accounts and other financial services, photos and many other sensitive personal data. If we change PCs, all this data will be destroyed forever, making them unrecoverable even with the most advanced recovery tools.

If we really want to empty the hard disk of all data and prevent our files from being recovered, in this guide we will show you how to format a hard disk or SSD to permanently erase everythingso you can reuse a drive on another computer or even resell it.

READ ALSO -> How to format a disk in Windows 11

1) Quick format from Windows

If the disk in question needs to be reused on our machines (so it doesn’t leave the house), we can quickly format it without wasting too much time using the formatting tool available within Windows.
We connect the disk to be formatted as secondary on our PC (either using another SATA port or connecting it as external USB disk)let’s start Windows and go inside File Explorer o Explorer.

Once we open this window, let’s open it This PC o Computer resourceswe identify the secondary disk connected just now (we can take help from the capacity and any files already present), we right-click on its icon and finally click on In format.

A new window will now appear where you can choose the file system to use (we recommend NTFS) and where to check the item Quick formatting; as soon as we are ready we click on the button Start.

Using quick formatting the disk will be immediately available and will appear empty to any operating system; however, it only erases the boot sector and the partition table, leaving all other files intact and accessible through specialized software. It is therefore not the best procedure if we have to sell or give the disk or the entire PC to someone else, since the files can be easily recovered.

2) Quick format from CCleaner

If we connect the hard disk to a case HDD USB or we have a external hard drive to delete we can also use CClenaer to effectively erase all contents, thus avoiding subsequent recovery.

After connecting the external disk and downloading the program to the PC, open CCleaner from the Start menu and go to the menu Instrumentswe press on the item Clean drivewe select Entire drive nel menu Emptywe indicate Advanced Overwrite (3 passes) next to the menu Safetywe tick the disk to be deleted in the list and finally press on Clean up.

The process can last hours but in the end we will have a perfectly “clean” disk, without any recoverable trace of the files present inside it.

2) Advanced formatting from PowerShell

If we need to empty a disk connected to the PC or secondary we can also use the formatting mode from PowerShell, very effective and safe to apply on any external disk or on any connected external drive.

In Windows 11 and Windows 10 we open Powershell from the Start menu (by pressing on the item Run as administrator sideways or by right-clicking on the menu item) and type the following command:

Format X: /P:5

Instead of X, we will have to put the identification letter of the disk to be deleted; if we have problems with drive letters on Windows we can read the guide above how to assign / change letter to disk drives, external drives, USB sticks.

3) Advanced formatting tool

To delete all data without the possibility of recovery we can use an external program that does the low level formattingalso called “disk reinitialization“; this process sets all binary values ​​to zero and erases a hard drive completely.

HDD Low Level Format Tool

The best free program that we can use to format a hard drive is definitely HDD LLF Low Level Format Tool.

To use it, simply connect the disk to be formatted as secondary to our PC (USB or another SATA connector), open the program and select the correct disk, taking help from the indications in the fields MODEL e CAPACITY. Once we have identified the disk, we click on Continue and confirm where necessary, so as to start the low-level formatting process. This operation (very long, it can take more than 4 hours) will replace each sector of the disk with 0s (zeros), so as to make the data contained within completely unrecoverable.

At the end, the disk will appear as unpartitioned and uninitialized, ready to be sold or given to users we don’t know. This program is available for free, but has an automatic speed limiter (180 GB per hour at 50 MB/s), which prevents its massive use; to unlock maximum speed it may be useful to purchase a user license, but if we are not in a hurry we can let the program work all night and wait for the end of the process without problems.

Darik’s Boot And Nuke o DBAN

A free program that formats your PC’s main drive deleting everything completely and definitively is Darik’s Boot And Nuke o DBAN, which works on any computer with an Intel or AMD processor and on Apple Mac machines. The program to download is an ISO image to burn onto a CD. Once the DBAN CD has been inserted into the computer, restart it and start it from the CD disk using the boot option from the bios (usually with the F12 key when the white writing on a black background appears at the beginning).

In the screen that appears, press Enter and wait for the program to load. On the next screen you can choose which disk you want to erase and format by selecting it with the space bar. To start the deletion process, you press F10.

With the M key you choose a deletion mode always based on the passes to be carried out. For any expert in the sector, DBan is the best program for deleting files from a hard disk without the possibility of recovering them, even better than paid programs. While very easy to use, the complete deletion process can be very time consuming.

KillDisk Freeware

If you wanted a Completely free program to definitively and permanently erase all data on the disk or any removable USB mediawhich can be used on Windows PC, Linux or Mac, without the need to create a boot CD, therefore just with an executable to runyou can try KillDisk.

To learn more we can read the guide on how initialize and format new or unrecognized disk (Windows).

4) Format disks with Linux stick

Another effective method to carry out true low-level formatting involves using Linux and it can also be used without removing the disk from the PC or notebook that we intend to give away (which is necessary to use the program shown previously).

First we install any GNU/Linux distribution on a USB stick, so as to be able to operate outside the operating system present on the disk to be formatted; to do this we download a GNU/Linux distribution in ISO format (like Ubuntu for example) and let’s see how to proceed by reading our guide on how install a Linux ISO on USB.

After preparing the stick with Linux, place it on a free USB port on the PC and restart the PC by setting the boot mode on the stick; if we don’t know how to do it, we can read an easy guide we created on the topic -> How to change the boot order of your computer.

Once we reach the main screen of the Linux operating system (which will start from the stick), we open the menu at the top right or the menu at the bottom left (depending on the Linux system downloaded) and look for the program Terminal o Terminal.

A kind of prompt will open (even if it is not a correct term, it resembles it very closely) in which to type the commands to low-level format the disk on the PC. Let’s start typing the command to see the connected disk in detail, so as to recover a fundamental code for formatting:

sudo fdisk -l

After launching this command, the terminal will show us verbatim information about the disk and any partitions present. For formatting we recover the code present in the string “Disk /dev/sda” where there is the path to the hard disk associated with the computer we are using.
After obtaining this information, we run the following command based on the information obtained from the previous command:

dd if=/dev/zero of=/dev/sda bs=512

In the place of of=/dev/sda we will have to use the precise path of the disk as recognized by Linux.
After launching this command, the disk in question will be formatted and each sector of the disk will be filled with 0s (zeros), thus making the disk completely unrecoverable.

Also in this case the process is very long (even over 5 hours), so it is better to leave it to act overnight; at the end we will have a disc like new and ready to be sold or given to third parties.

5) Complete formatting of SSD and M.2 drives

The programs and steps shown so far are fine for mechanical disks, but are unnecessary for SSDs and NVMe M.2given that the latter are extremely sensitive to very intense writing processes (and previous programs write continuously for several hours, effectively shortening the life of the SSD).

To completely format an SSD, simply erase it with quick format as seen in the first point of the guide and delete any traces using the TRIM command, used by default to remove residual data present within the cells.

To start this command we connect the SSD to be formatted as a secondary disk via USB or internal drive (with SATA), open the Windows Start menu and search Defragment and optimize drives.
The disk management system will open: identify the SSD among the disks present, select it and finally click on the bottom Optimize.

The SSD is now fully formatted and any traces deleted from the cells, making file recovery difficult. Alternatively we can erase the SSDs using the tools made available by the various solid state drive manufacturers, who also offer a drive management and erasure tool.
For example, SanDisk offers the free tool for its SSDs SanDisk SSD Dashboard.

Once installed on the system (where we have previously connected the SanDisk SSD to be formatted), let’s go to the menu Instruments and then on Erase drive.

Software per SSD

If we use other types of solid state drives, we can download the relevant ones tool per SSD which we have already talked about, among which there are:

• Samsung Magician SSD
• Toshiba SSD Utility
• Intel Memory and Storage Tool

We use the right tool based on the type of SSD or M.2 used.

Conclusions

If you intend to permanently delete only some files, without carrying out complete formatting, you can use i programs to delete files safely and permanently; alternatively we can erase free disk space without touching the other files and without formatting.

Still talking about hard drives, in other articles we have highlighted the best ones programs to check the health of the disk and those for the check errors with scandisk or checkdisk su Windows.