cal calendar command for terminal

You can use the cal command to display a calendar in Julian or Gregorian format. The format depends on your locale settings but can be toggled with parameters.

As the screen below shows the default calendar is the current month. You can use the parameter -A 2 to display the next two months or 2018 to display all months in that year:

Ubuntu versions after 20.04

After version 20.04 you may have to use

sudo apt update
sudo apt install ncal

Note the ncal package does include the cal command. Also note that ncal is available out of the box in earlier Ubuntu versions before 20.04 as well.

For example on Ubuntu 16.04 LTS ECM:

$ ncal

    March 2022        
Su     6 13 20 27   
Mo     7 14 21 28   
Tu  1  8 15 22 29   
We  2  9 16 23 30   
Th  3 10 17 24 31   
Fr  4 11 18 25      
Sa  5 12 19 26      

An alternative is ncal - this displays the calendar in a vertical format, i.e.:

    March 2017
Su     5 12 19 26
Mo     6 13 20 27
Tu     7 14 21 28
We  1  8 15 22 29
Th  2  9 16 23 30
Fr  3 10 17 24 31
Sa  4 11 18 25

This is slightly harder to read, but supposedly has the advantage that the full year's calendar, by putting four months in each row, fits in a standard sized terminal. In fact, it does not, you have to remove blank lines from the output for it to fit in 24 lines: ncal 2017 | grep -v '^$'. The original version of ncal did not have these blank lines. In any case, it takes less vertical space than the traditional calendar output - 26×76, vs 35×66 for cal.

Khal is a calendar application that's much more along the lines of what someone might expect in the year 2020:

It can be installed via pip3 install khal (or just pip instead of pip3). It supports a standard CalDav format and can by synced to a CalDav server. Additionally it includes an interactive tool (ikhal or khal interactive) (sort of like tig for git) for viewing and editing events in an easier way without having to remember all the flags and syntax and everything.

Programmable Calendars

Although these are GUI calendars you can still call them from the terminal. They allow you to navigate through the months and years. They are designed to be called from your Bash scripts but like all Bash commands you can call them from the terminal too.

YAD (Yet Another Dialog) super-charged fork of Zenity

Zenity GUI fork of text-based dialog

Do not be concerned by the Gtk warning message. You see that a lot when running GUI programs from the terminal. eg. gedit and nautilus display similar warnings.

Another alternative to the standard cal is an enhanced cal by Alex Matulich. It offers user-configurable colors and the ability to display reminders and appointments next to the calendar.

Enhanced cal page on Unicorn Research site

Edit 2022-06-01: It's available in the repos with sudo apt install ccal.

use cal command for default calendar. also you can install jcal package for jalali calendar.