How to Change Time Format in Ubuntu: 12h or 24h
You change the time format in Ubuntu by adjusting your system’s regional settings.
This process allows you to switch between the 12-hour (AM/PM) and 24-hour (military time) display for your clock, which is useful if you have a preference or specific requirement, like a default 24-hour format you’re accustomed to.
For example, many users find the 12-hour format more intuitive for daily use, while others need the precision of the 24-hour format for professional tasks. This quick adjustment ensures your clock display matches your needs across your Ubuntu desktop, typically updating the top bar clock instantly.
Open Settings, go to System, then Date & Time, and select your preferred Time Format from the dropdown. Alternatively, use the terminal command gsettings set org.gnome.desktop.interface clock-format 12h or 24h.
Quick Settings Menu
Modern versions of Ubuntu include a “Quick Settings” menu. This is the fastest way to access your clock settings. Click the group of icons in the top-right corner of your screen (where the volume and battery icons are). You can often click directly on the time or the gear icon to jump into your configuration options.
Change system time format using the Settings app
Ubuntu keeps most of your settings in one central place. To open it, click the Activities button or press the Super key, then type Settings.
Alternatively, click the Quick Settings menu at the top-right and select the gear icon.
In the Settings sidebar, scroll down and click on System, then select Date & Time.
Look for the Time Format section. Click the drop-down menu to choose between 24-hour or AM/PM.
Your choice takes effect instantly.
Change system time format using the command terminal console
You can also use the terminal to change your clock settings. Note: These commands work with GNOME, the default desktop environment for Ubuntu.
Open the terminal by pressing Ctrl+Alt+T.
To set your clock to a 12-hour format, type this command and hit Enter:
gsettings set org.gnome.desktop.interface clock-format 12h
To switch back to a 24-hour format, type this command and hit Enter:
gsettings set org.gnome.desktop.interface clock-format 24h
Change system time format using the Dconf Editor
For those who prefer a visual tool for advanced settings, Dconf Editor is an option. If you’re familiar with Windows, it’s a bit like the Windows Registry Editor.
Disclaimer: Dconf Editor is an advanced tool that allows you to change low-level system settings. It is not recommended for basic users as incorrect changes can affect your system stability.
You must install this tool first. Learn how to install software here: How to add or remove software on Ubuntu Linux.
After launching Dconf Editor, navigate to this path:
org -> gnome -> desktop -> interface -> clock-format
Flip the “Use default value” switch off. Then, type ’12h’ or ’24h’ into the Custom value box to set your preference.
Conclusion
You now know how to toggle your time display using the Settings app, the terminal, or the Dconf Editor. Choose the method that feels most comfortable for you.
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About the Author
Richard
Tech Writer, IT Professional
Richard, a writer for Geek Rewind, is a tech enthusiast who loves breaking down complex IT topics into simple, easy-to-understand ideas. With years of hands-on experience in system administration and enterprise IT operations, he’s developed a knack for offering practical tips and solutions. Richard aims to make technology more accessible and actionable. He's deeply committed to the Geek Rewind community, always ready to answer questions and engage in discussions.
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