Cron Second Field

The second field is prepended by Azure Functions (NCRONTAB) and Quartz Scheduler. Standard 5-field Linux cron does not have a seconds field — the minimum interval is one minute.

Quick Reference
ValueMeaningExample
0At exactly :00 seconds (no offset)0 */5 * * * *
30At the 30-second mark30 * * * * *
*/10Every 10 seconds (Azure/Quartz only)*/10 * * * * *
*Every second (runs 60 times per minute!)* * * * * *
0,30At :00 and :30 seconds — twice per minute0,30 * * * * *

Valid Values

0

Minimum

59

Maximum

* , - /

Allowed special characters

Examples

0Zero-second offset — fires at exactly :00 of each scheduled minute
*/30Every 30 seconds (Azure/Quartz only)
*/10Every 10 seconds (sub-minute scheduling)

Platform Support

Platforms that include the Second field:

Azure Functions (NCRONTAB)Quartz SchedulerSpring @Scheduled

Frequently Asked Questions

Why doesn't standard Linux cron have a seconds field?
Standard cron was designed for minute-granularity scheduling. The cron daemon wakes up once per minute. For sub-minute jobs, use a process manager (systemd with OnCalendar=*:*:0/10), Quartz, or a language-level scheduler.
How do I run a job every 30 seconds in Quartz?
Use "0,30 * * * * ?" — the seconds field accepts comma-separated values. This fires at the 0-second and 30-second mark of every minute.
Built & maintained by Danny Vargas
Last updated January 2026·Parsing runs in your browser — no expression leaves your device