Debian Locale and Timezone

Configure language, character encoding, and time settings for your system.

Show current timezone:

timedatectl

List available timezones:

timedatectl list-timezones
timedatectl list-timezones | grep America

Set timezone:

sudo timedatectl set-timezone America/New_York
sudo timedatectl set-timezone Europe/London
sudo timedatectl set-timezone UTC

Or manually:

sudo ln -sf /usr/share/zoneinfo/America/New_York /etc/localtime

Check timezone file:

cat /etc/timezone

Enable network time sync (NTP):

sudo timedatectl set-ntp true

Show sync status:

timedatectl

Manually set time:

sudo timedatectl set-time "2024-01-15 14:30:00"

Show current locale:

locale

List available locales:

locale -a

Set system locale:

sudo update-locale LANG=en_US.UTF-8
sudo update-locale LC_TIME=en_GB.UTF-8

Reconfigure locales:

sudo dpkg-reconfigure locales

Then select locales to generate. Changes take effect after logout/login.

Show current:

setxkbmap -query

Set temporarily:

sudo loadkeys us

Persistent configuration:

sudo dpkg-reconfigure keyboard-configuration

Then restart:

sudo systemctl restart keyboard-setup

• LANG — default language
• LC_TIME — date/time format
• LC_NUMERIC — number format (. vs ,)
• LC_MONETARY — currency symbols
• LC_COLLATE — sorting order
• LC_CTYPE — character classification
• LC_MESSAGES — error messages
• LC_PAPER — paper size (A4, Letter)

Each can be set independently:

export LC_TIME=de_DE.UTF-8
date           # shows German date format

• en_US.UTF-8 — US English, UTF-8
• en_GB.UTF-8 — British English
• de_DE.UTF-8 — German
• fr_FR.UTF-8 — French
• ja_JP.UTF-8 — Japanese
• C.UTF-8 — POSIX locale (useful for scripts)

Most modern systems use UTF-8; avoid older encodings (ISO-8859-1, etc.).

• Servers usually use C.UTF-8 or en_US.UTF-8
• Locale affects sorting in ls, collation in databases
• Always set locale before user environment to avoid surprises