title: "Understanding WP-Cron Scheduling" post_status: publish comment_status: open taxonomy: category: - developer-plugins-handbook post_tag: - Understanding Wp Cron Scheduling - Cron - Repos

Understanding WP-Cron Scheduling

Unlike a traditional system cron that schedules tasks for specific times (e.g. "every hour at 5 minutes past the hour"), WP-Cron uses intervals to simulate a system cron.

WP-Cron is given two arguments: the time for the first task, and an interval (in seconds) after which the task should be repeated. For example, if you schedule a task to begin at 2:00PM with an interval of 300 seconds (five minutes), the task would first run at 2:00PM and then again at 2:05PM, then again at 2:10PM, and so on, every five minutes.

To simplify scheduling tasks, WordPress provides some default intervals and an easy method for adding custom intervals.

The default intervals provided by WordPress are:

• hourly
• twicedaily
• daily
• weekly (since WP 5.4)

Custom Intervals

To add a custom interval, you can create a filter, such as:

add_filter( 'cron_schedules', 'example_add_cron_interval' );
function example_add_cron_interval( $schedules ) { 
  $schedules['five_seconds'] = array(
    'interval' => 5,
    'display'  => esc_html__( 'Every Five Seconds' ),
  );
  return $schedules;
}

This filter function creates a new interval that will allow us to run a cron task every five seconds.

[info]All intervals are in seconds.[/info]