Customize the core Calendar block time format

The default time format for the core Calendar block depends on the locale, but you can customize it using a custom block template. In the custom block template you can add a timeFormat property option with the time format you prefer.

Steps to customize the default calendar time format:

• copy view.php
  concrete\blocks\calendar\view.php
• navigate to application\blocks and create a folder called "calendar"
  application\blocks\calendar
• inside the "calendar" folder, create a folder called "templates"
  application\blocks\calendar\templates
• paste view.php into the "templates" folder
  application\blocks\calendar\templates\view.php
• rename view.php to "custom_time_format.php"
  application\blocks\calendar\templates\custom_time_format.php
• open custom_time_format.php and look for the .fullCalendar() method call
• directly below the .fullCalendar() method call, paste in the timeFormat: 'hh:mma', option and value

• after pasting the timeFormat option and value, the top portion of the .fullCalendar() method call should look like this

  $('div[data-calendar=<?=$bID?>]').fullCalendar({
      timeFormat: 'hh:mma',
      header: {
  

• you can now apply the "Custom Time Format" custom block template to your Calendar block to display the custom time

Example time format values:

timeFormat: 'H(:mm)', // 22:30 or 23  
timeFormat: 'h(:mm) t', // 10:30 p or 11 p  
timeFormat: 'h(:mm)t', // 10:30p or 11p  
timeFormat: 'h:mm', // 10:30 or 11:00  
timeFormat: 'hh:mma', // 10:30pm or 11:00pm  
timeFormat: 'hh:mm a', // 10:30 pm or 11:00 pm  
timeFormat: 'hh:mmA', // 10:30PM or 11:00PM  
timeFormat: 'hh:mm A', // 10:30 PM or 11:00 PM  

Setting a timeFormat property option will affect all views.
https://fullcalendar.io/docs/text/timeFormat

The time format can also be set on a per view basis.
https://fullcalendar.io/docs/views/View-Specific-Options