Every hour on the half

Why this pattern

30 * * * * runs once per hour, at minute 30. Useful when you want hourly cadence but specifically do not want to compete with the top-of-hour spike that everybody else schedules at 0 * * * *.

Variations

• Top of the hour: 0 * * * * or @hourly
• Quarter-past: 15 * * * *
• Twice an hour: 0,30 * * * *

Platform notes

Most managed schedulers (AWS, GCP Cloud Scheduler, Vercel) are tolerant of off-hour minutes and there is no performance penalty. Linux cron users sometimes prefer this pattern because the system logrotate and many distro-provided cron jobs fire on the hour, and you want to step out of their way.