Using the 'cal' Command to Display Calendar Information (with examples)

The cal command is a useful tool for displaying calendar information in the terminal. It allows you to view calendars for the current month, previous and next months, specific months and years, and even calculate the date of Easter for a given year. In this article, we will explore different use cases of the cal command with code examples, motivations, explanations, and example outputs.

1: Display a calendar for the current month

Code: cal

Motivation: This use case is helpful when you quickly want to view the calendar for the current month without any additional specifications.

Explanation: Simply typing cal in the terminal will display the calendar for the current month. It will show the current date highlighted.

Example Output:

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

2: Display previous, current, and next month

Code: cal -3

Motivation: This use case is helpful when you want to get an overview of the calendar for the previous, current, and next month.

Explanation: The -3 option displays the calendar for the previous month, current month, and the next month. It shows the month names at the top and the corresponding dates in a grid format. The current date is highlighted.

Example Output:

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

3: Display a calendar for a specific month

Code: cal -m month

Motivation: This use case is helpful when you want to view the calendar for a specific month.

Explanation: By specifying a month using the -m option, you can display the calendar for that particular month. The month can be specified using either a number (1-12) or the name of the month (e.g., “December”).

Example Output:

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

4: Display a calendar for the current year

Code: cal -y

Motivation: This use case is helpful when you want to view the calendar for the entire current year.

Explanation: By using the -y option, you can display the calendar for the current year. It will show each month of the year with the corresponding dates.

Example Output:

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

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

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

5: Display a calendar for a specific year

Code: cal year

Motivation: This use case is helpful when you want to view the calendar for a specific year.

Explanation: By specifying a year (in four digits), you can display the calendar for that particular year. It will show each month of the specified year with the corresponding dates.

Example Output:

                            2023
      January               February               March
Su Mo Tu We Th Fr Sa   Su Mo Tu We Th Fr Sa   Su Mo Tu We Th Fr Sa
 1  2  3  4  5  6  7                1  2  3                1  2  3
 8  9 10 11 12 13 14    4  5  6  7  8  9 10    4  5  6  7  8  9 10
15 16 17 18 19 20 21   11 12 13 14 15 16 17   11 12 13 14 15 16 17
22 23 24 25 26 27 28   18 19 20 21 22 23 24   18 19 20 21 22 23 24
29 30 31               25 26 27 28             25 26 27 28 29 30 31

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

6: Display a calendar for a specific month and year

Code: cal month year

Motivation: This use case is helpful when you want to view the calendar for a specific month and year.

Explanation: By specifying a month and year, you can display the calendar for that particular month in the specified year. The month can be specified using either a number (1-12) or the name of the month (e.g., “December”).

Example Output:

   December 2023   
Su Mo Tu We Th Fr Sa
                1  2
 3  4  5  6  7  8  9
10 11 12 13 14 15 16
17 18 19 20 21 22 23
24 25 26 27 28 29 30
31

7: Display date of Easter (Western Christian churches) in a given year

Code: ncal -e year

Motivation: This use case is helpful when you want to calculate the date of Easter (according to the Western Christian churches) for a specific year.

Explanation: By using the ncal command with the -e option and specifying a year, you can calculate and display the date of Easter for that particular year.

Example Output:

Easter Sunday is on April 9, 2023

In this article, we have explored different use cases of the cal command with code examples, motivations, explanations, and example outputs. With the flexibility provided by various options, you can effectively utilize the cal command to view and calculate calendar information as per your needs.