Crontab syntax basics, and how it differs from WP-Cron

"What does */5 * * * * actually mean?" — anyone setting up a scheduled task on a server has probably stared at that row of asterisks at some point. If you run WordPress, you may already be familiar with inspecting WP-Cron's internals through WP-CLI, but the actual crontab syntax used by the OS itself is something many people never learn properly. Before you can switch WP-Cron over to a real OS-level cron job, you need to understand that syntax first.

Note: crontab is a scheduling mechanism built into Unix-like systems (Linux, macOS, etc.). The name is short for "cron table" — a configuration file, and the command used to manage it, that lists what to run and when, one line at a time.

The five time fields

Each line in a crontab consists of five time fields followed by the command to run.

minute hour day month weekday command

Crontab syntax basics, and how it differs from WP-Cron

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