Kubuntu Focus: ISO Verification

ISO Verification

Ensure correct ISO downloads

This page provides instructions for verifying the integrity of ISO files on all popular operating systems. We highly recommended you verify the Kubuntu Focus Suite ISO file immediately after download. This helps ensure you will not encounter corruption or stability issues during installation.

Verifying KFocus Suite ISOs
Verifying other ISOs
Revisions
Disclaimer

Verify a Kubuntu Focus Suite ISO with Dolphin.

Please read the disclaimer before proceeding. We review and update guided solutions regularly. If you have suggestions or requests, please write support@kfocus.org.

Verifying KFocus Suite ISOs

This guide explains how to verify a Kubuntu Focus Suite ISO using a Kubuntu Focus system.

Download the ISO. The current latest ISO is kubuntu-focus-24.04.3-2025.09.20-desktop-amd64.iso.
Open Dolphin and navigate to the folder where you downloaded the ISO. The default is usually Downloads under your home directory.
Right-click on the ISO file and click Properties.
Click the Checksums tab and paste the following checksum into the expected checksum field: 5274fddc84f45168d00e3563f42b70c09c39d67597ff0b635991880a1cb72258
Dolphin will automatically calculate the checksum of the ISO. Wait for this process to complete.
If the checksums match, your ISO is good. Proceed to the Clean Install guide.
If the checksums do not match, your ISO is bad. Delete it and download it again.

Verifying other ISOs

The following instructions are useful for verifying ISO files on any major OS.

Linux (with the verification file)

Many ISOs have a verification hash file provided alongside them. When this is the case, most Linux systems can verify that the ISO is intact with one command, using the sha256sum tool. To do this:

Download the ISO file and its accompanying verification hash file. This file is usually named SHA256SUMS or iso-file.sha256.
Open a terminal emulator.
Using the cd command, navigate to the folder where the ISO and verification hash files are located. This will usually be ~/Downloads.
Run sha256sum -c verification-file.sha256 |& grep OK, replacing the name verification-file.sha256 as needed.
If you see a line of output similar to iso-file.iso: OK, your ISO download is good.
If you do not see any output whatsoever, or if all output refers to files other than the ISO file you downloaded, your ISO download is bad and should be deleted. If this is the case, download the ISO again.

Linux (without a verification file)

Sometimes the verification hash for an ISO file is provided as a string, rather than as a separate file. When this is the case, you can verify the ISO file using the following procedure:

Download the ISO file.
Open a terminal emulator.
Using the cd command, navigate to the folder where the ISO is located. Often this will be ~/Downloads.
Run if [ 'VERIFICATION-HASH-HERE' = "$(sha256sum iso-file.iso | cut -d' ' -f1)" ]; then echo 'Good'; else echo 'Bad'; fi, replacing iso-file.iso and VERIFICATION-HASH-HERE as needed.
If you see a line of output that says Good, your ISO download is good.
If you see a line of output that says Bad, your ISO download is bad. It should be deleted and downloaded again.

Windows

Most versions of Windows provide the certutil utility, which can check ISO file verification hashes. To do this:

Download the ISO file.
Open Explorer (the file manager application in Windows).
Navigate to the folder where you downloaded your ISO. Usually this will be Downloads.
Press [ALT][D] on your keyboard. This will highlight the address bar at the top of the window.
Type cmd and press Enter. A command prompt window will open. Any commands run from here will run in the current folder.
Inside the command prompt window, run certutil -hashFile "iso-name.iso" SHA256, replacing iso-name.iso as needed. The command will process for a while, then output a sequence of numbers and letters.
Look at the hash provided alongside the ISO file (either by opening the verification hash file in your browser or text editor, or by viewing the page that displays this hash). Carefully compare it to the sequence of numbers and letters output by certutil.
If the file hashes match, your ISO download is good.
If the file hashes do not match, your ISO download is bad. It should be deleted and downloaded again.

macOS

macOS provides the shasum utility, which can check ISO file verification hashes. To do this:

Download the ISO file.
Open Terminal (the default terminal emulator in macOS).
Open Finder (the default file manager in macOS) and navigate to the folder where your download is located. Usually this will be Downloads.
In Terminal, type shasum -a 256 (including a space at the end), then drag and drop the ISO file from the Finder window into the Terminal window. The full path to the ISO file will automatically appear in Terminal.
Press Enter. The command will process for a while, then output a sequence of numbers and letters.
Look at the hash provided alongside the ISO file (either by opening the verification hash file in your browser or text editor, or by viewing the page that displays this hash). Carefully compare it to the sequence of numbers and letters output by certutil.
If the file hashes match, your ISO download is good.
If the file hashes do not match, your ISO download is bad. It should be deleted and downloaded again.

Revisions

This is a partial revision history. See the git repository for all entries.

2025-04-29 73f68747 ISO release updates
2025-04-19 274c0ff1 Update grammar and content per audit
2025-03-31 003d5bb2 Remove tab characters
2025-01-09 5fea468e ISO release updates
2024-12-06 35123b93 Normalize Hints Widget name and keyboard shortcut format
2024-09-25 d6f82bd3 ISO release updates
2024-09-10 73fcff02 Fix minor issues
2024-08-29 2fc5df2b ISO release updates
2024-08-19 57a2389d Add white theme
2024-07-28 ee7b4601 Update metadata content, collapsable sections, lightbox
2024-07-26 7814a97d Sync primary images between guided solutions slideshow and articles
2024-07-24 f6fedad2 Add Lightboxes
2024-07-22 729996c3 Release ISO 24.04 LTS
2024-07-21 9148396d Fix lightbox includes on iso-verify
2024-07-19 14b82268 Initial release

Disclaimer

We try hard to provide a useful solution validated by professionals. However, we cannot anticipate every situation, and therefore cannot guarantee this procedure will work for your needs. Always backup your data and test the solution to determine the correct procedure for you.

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