Cron expression `*/30 1 18 JUN 1-5` runs every 30 minutes, between 01:00 and 01:59, on day 18 of the month, Monday through Friday, only in June

Read more in the dedicated guide: Cron every 30 minutes.

What this cron means, field by field

Each field of */30 1 18 JUN 1-5 controls one dimension of the schedule. Hover over any value in the editor above to see its tooltip; the table below summarises the same information.

Field	Value	Means	Range / hint
minute	`*/30`	every 30 minutes	0-59. The minute(s) of the hour the job will fire.
hour	`1`	at hour 1	0-23. The hour(s) of the day the job will fire (0 = midnight, 23 = 11 PM).
day of month	`18`	at day of month 18	1-31. The day(s) of the month. Use * if you want every day.
month	`JUN`	at month JUN	1-12 or JAN-DEC. The month(s). Use * for every month.
day of week	`1-5`	from day of week 1 through 5	0-7 or SUN-SAT (0 and 7 both mean Sunday). Use * for every day of the week.

Next 5 runs

Shown in UTC. Change the timezone in the editor.

Next runs · UTC

Tue 1 Jun · 01:00in 257d 11h
Tue 1 Jun · 01:30
Wed 2 Jun · 01:00
Wed 2 Jun · 01:30
Thu 3 Jun · 01:00

Similar cron expressions

Common variations and tweaks of */30 1 18 JUN 1-5.

Where else this cron could be used

The same expression */30 1 18 JUN 1-5 works in:

Standard Unix crontab (5-field syntax).
AWS EventBridge / Lambda Scheduled (with a 6th field for year, often *).
Vercel cron jobs (declared in vercel.json).
Quartz Scheduler and node-cron, robfig/cron and similar libraries.

Examples

0 18 * * *
Every day at 18:00
0 */5 * * *
Every 5 hours
0 18 * * 1-5
Weekdays at 18:00
0 0 1 * *
Once a month, on the 1st at midnight

Cheatsheet

Full cheatsheet

Field	Req.	Range	Wildcards
minute	yes	0-59	, - * /
hour	yes	0-23	, - * /
day of month	yes	1-31	, - * /
month	yes	1-12 or JAN-DEC	, - * /
day of week	yes	0-6 or names; some dialects use 0-7 or 1-7 — see Dialects	, - * /

Frequently asked questions

What does the cron expression `*/30 1 18 JUN 1-5` mean?

every 30 minutes, between 01:00 and 01:59, on day 18 of the month, Monday through Friday, only in June.

When does `*/30 1 18 JUN 1-5` run next?

The next runs (UTC): 2027-06-01 01:00; 2027-06-01 01:30; 2027-06-02 01:00; 2027-06-02 01:30; 2027-06-03 01:00.

Is `*/30 1 18 JUN 1-5` a valid cron expression?

Yes - CronTool's parser accepts this expression and the calendar projects future runs successfully.