How to Install Debian Step by Step
With the netinst image, including the recent change that already includes needed non-free firmware by default.
Step 1: choosing and downloading the correct image
The netinst (network install) image is the recommended one for most cases — it downloads only the bare minimum needed and gets the rest during installation, requiring an internet connection.
Important update: since Debian 12, the official images (including netinst) can already include non-free firmware packages needed for common wifi or graphics hardware — if you see older guides recommending you look for a separate "unofficial image with firmware included", that extra step is no longer needed on recent versions.
Step 2: creating the bootable USB drive
Use Rufus (Windows) or Balena Etcher (any system) to write the downloaded ISO image onto a USB drive of at least 1 GB.
Step 3: the installer
- Boot from the USB drive → choose "Install" (faster, no graphical interface) or "Graphical install" (more visually comfortable).
- Language, location, keyboard layout.
- Machine name and network configuration (automatic in most cases).
- Create the root password and your personal user.
- Partitioning — "Guided, use entire disk" is the simplest option for a new machine dedicated to Debian.
- Software selection: choose a desktop environment (GNOME by default) and the standard system utilities.
Tip: if during installation a device requests firmware that isn't found, the installer offers to load it from an additional USB drive — you can continue without it if you know that particular device isn't essential during the installation itself (for example, wifi, if you have an Ethernet cable available).
After installing
Update the system as soon as you first log in, and consider customising the desktop to your liking.
Frequently asked questions
Do I need to look for a special image for my wifi to work?
Since Debian 12, it's no longer necessary in most cases — the official images (including netinst) can include the non-free firmware needed for common hardware directly.
What's the difference between 'Install' and 'Graphical install'?
Both install the same final system — 'Graphical install' offers a more visual interface during the process, while 'Install' uses text, being slightly faster on very limited machines.