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Getting Familiar With Debian Releases

Refer to Debian Releases for more information about the Debian versions, but the following ideas may guide your decision.


The whole point of Debian from day one was "Stable", in reaction to what else was extant at the time: SoftLandingSystems "SLS" and Slackware. Debian chose stability, as administrators needed for servers. Choose Debian "Stable" if you want the computer to just work for a prolonged period of time, without the risk of new packages breaking your habits or workflow. In most cases, when people talk about Debian, they are referring to Debian "Stable". The network install images for stable (bookworm) can be found at


If it is important to you to have recent packages of all the installed software continuously rolling through Debian, and you are fine with constantly downloading and installing updates that will stir up a bug at times, and you want to help squash bugs threatening to get into Stable, you may choose Debian "Testing". The network install images for testing (trixie) can be found at


Security note

Unstable exclusively gets security updates through its package maintainers.
The Debian Security Team only maintains security updates for the current "stable" release.
If timely and official security updates are of any importance to your use case, do not migrate to Unstable.

If it is important to you to have the absolute latest packages available in Debian, you should learn about Debian "Unstable". There are currently no network install images for Unstable. If you want to install Unstable, download the image for Stable and upgrade through Testing to Unstable by editing /etc/apt/sources.list.

Choosing The Appropriate Installation Media

Be sure you have downloaded the installer for your hardware architecture. (The i386 architecture is for both Intel and AMD 32 bit CPUs. The amd64 architecture is for both Intel and AMD 64 bit CPUs.) The amd64 architecture is appropriate for most common hardware.

There are two main choices of installation media to meet your needs:

The Network Install Image

For those with reliable Internet access using a network install image often saves time, compared with downloading some of the 650 MB ISO images. This network install ISO (called "netinst") contains only a near-minimal Debian system. During installation as many packages as you request are downloaded from the Internet. A netinst ISO image is several hundred MB but the CD or DVD images are much larger and will almost surely contain packages which are downloaded but not installed by default.

If your wireless network card is not recognized by the installer you might consider performing the installation using a wired (Ethernet cable) connection or installing using a different network card. In any case it may be preferable to install with a wired connection for bandwidth reasons or simply to defer wireless setup until after the initial installation.

If you have no way of establishing a network connection while installing then you will need to install using at least a partial set of the installation CDs or DVDs (at least Disc 1).

The Full "CD/DVD" Image

These images are for those who need all available packages that are in the current "stable" release of Debian.

Although there are over 30 CDs (or 5 DVDs) in a full set, only the first CD or DVD is required to install Debian. The additional images are optional and include extra packages, that can be downloaded individually during the installation, or later.

Non-Free Firmware

Since bookworm, non-free firmware is allowed to be included in the official installation media, so firmware should be no problem anymore for installation.

Please refer to the Firmware Page for details.

Debian Live images

Alternatively to the installation images mentioned above there are Live install images available.

They can start the usual debian-installer from the boot menu, but their main goal is the Live system, which starts a real Debian system directly from the iso image, without installation on your harddisk.

With this Live system, you can easily give Debian a try, and also test how well Debian interacts with your hardware.

And then there is the Calamares installer, an end-user-friendly alternative to our good old debian-installer, to install Debian on your harddisk.

To get this running, choose one of the Live iso images from (it's your choice which you prefer, but don't choose the "standard" image for this purpose, since it has no graphical user interface), select Live system from the boot menu, and when the system is up choose "Install Debian" from the desktop.

The Calamares installer will guide you through the installation.

Creating a Bootable Debian USB Flashdrive

After downloading the .iso file, the next step is to create some form of bootable media that you can use to install Debian. The most common form of installation is from a USB flash drive. If you wish to use a CD or DVD, you can use that method as well.

To create a bootable USB drive from Microsoft Windows or Mac OS a usable choice is Rufus. Warning: Rufus has 2 writing modes "ISO" and "DD" mode, which you can select just before writing begins. For Debian installer images or Debian live images, you MUST select the "DD" writing mode -- ISO mode will alter the copy of the image on the target media (confirmed August 27, 2021, using rufus version 3.15).

To create a bootable USB drive on Linux follow the installation instructions. [TL;DR cp debian.iso /dev/sdX Be cautious!]

To burn the .iso to a CD on Microsoft Windows use IMGBurn or, if using Windows 10, the builtin "Burn to disc" option when right clicking an ISO file.

Booting From a USB Flash Drive

If you plan to dual-booting with another OS, both OSes' need to be installed with the same boot mode. Most computers built after 2012 boot in UEFI mode, so this configuration dictates use of UEFI mode when installing and booting Debian. If the other system of your computer are installed in BIOS(legacy) mode, then you must install Debian in BIOS mode as well.

You should be able to check the current boot mode in the first few seconds of your computer starting up. Some common options include the "F2", "F8", "F12", and "Del" keys.

Debian supports Secure Boot since the Debian buster release. If problems arise during the Debian installation or the first boot process (such as failing to boot the Linux Kernel at all and/or refusing to start Debian) turn off Secure Boot before attempting anything else. Moreover, a number of devices (commonly laptop computers) present subtle bugs/limitations when operating Linux under SecureBoot, which are not present otherwise. Make sure to check your device manufacturer's support pages.
Example: Lenovo Linux SecureBoot limitations

Once the proper boot mode is set, you are ready to start your installation. If the Debian Installer does not load, you may have to change your boot options and specify booting from USB.


Prior to making any major change to your computer you should ALWAYS backup all of your work. While the Debian Installer has been extensively tested, it cannot prevent you from making mistakes nor prevent a power failure while you are installing your new operating system.
Also, ALWAYS double check the disk you are formatting to install Debian on. Formatting another disk/partition results in unrecoverable data loss on that disk/partition.

Installation FAQ

Q: I am at the Software Selection screen in the Debian Installer, where I can choose a selection of desktop environments.
What is Debian desktop environment (the first choice)?
A: If you do NOT select any desktop environment and leave the default Debian desktop environment checkbox ticked,
you will install the GNOME desktop environment on your machine.
If you choose "Debian desktop environment" AND a specific desktop, the specific choice overrides the GNOME default.

Q: Why does my Wi-Fi not work during the installation process ?
A: If you are using a laptop computer, you might need proprietary firmware for your wireless network card to function, which Debian does not include by default.
Please refer to the "Non-Free Firmware" section above OR install Debian using a wired connection, if possible, and setup wireless after installing.

Post-Install Tips

$ su -l
# adduser USERNAME sudo
# exit

$ groups

$ sudo apt update && sudo apt upgrade

See also

ToDo | CategoryObsolete - this page needs a thorough rewrite