Cron: every 30 seconds
*/30 * * * * *: Every 30 seconds.
Meaning
Examples
Note
Six fields: the first is seconds. Classic crontab has no seconds field, so this works in Quartz, Spring, node-cron and similar schedulers, not in Linux cron.
Other common schedules
Seconds
- Every 10 seconds
*/10 * * * * * - Every 30 seconds
*/30 * * * * *
Minutes
- Every minute
* * * * * - Every 2 minutes
*/2 * * * * - Every 5 minutes
*/5 * * * * - Every 10 minutes
*/10 * * * * - Every 15 minutes
*/15 * * * * - Every 20 minutes
*/20 * * * * - Every 30 minutes
*/30 * * * *
Hours
- Every hour
0 * * * * - Every 2 hours
0 */2 * * * - Every 3 hours
0 */3 * * * - Every 4 hours
0 */4 * * * - Every 6 hours
0 */6 * * * - Every 8 hours
0 */8 * * * - Every 12 hours
0 */12 * * * - Every hour, 9am–5pm on weekdays
0 9-17 * * 1-5
Days
- Every day at midnight
0 0 * * * - Every day at 1am
0 1 * * * - Every day at 2am
0 2 * * * - Every day at 6am
0 6 * * * - Every day at 8am
0 8 * * * - Every day at 9am
0 9 * * * - Every day at noon
0 12 * * * - Every day at 5pm
0 17 * * * - Every day at 6pm
0 18 * * * - Twice a day
0 0,12 * * * - Every other day
0 0 */2 * *
Weeks
- Every weekday at 9am
0 9 * * 1-5 - Every Saturday and Sunday
0 0 * * 6,0 - Every week
0 0 * * 0 - Every Monday
0 0 * * 1 - Every Friday
0 0 * * 5 - Every Saturday
0 0 * * 6
Months and years
- Every month
0 0 1 * * - On the 15th of every month
0 0 15 * * - Every quarter
0 0 1 */3 * - Every 6 months
0 0 1 */6 * - Every year
0 0 1 1 *