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Quick Answer

A cron expression is 5 space-separated fields: minute hour day-of-month month day-of-week. 0 3 * * * means "3 AM every day". */5 * * * * means "every 5 minutes". Use the examples below as a starting point, paste into your scheduler, and double-check the timezone.

Cron Expression Builder & Reference

Pick a schedule, copy the expression. Or read the field reference and write your own. Built for the standard 5-field cron syntax used by Linux crontab and most hosted schedulers (including Requex).

Last updated: May 2026 • 7 min read

The 5 fields

┌───────── minute (0-59)
│ ┌─────── hour (0-23)
│ │ ┌───── day of month (1-31)
│ │ │ ┌─── month (1-12)
│ │ │ │ ┌─ day of week (0-6, Sunday = 0)
│ │ │ │ │
* * * * *
FieldRangeSpecial characters
Minute0-59*, /, -, ,
Hour0-23*, /, -, ,
Day of month1-31*, /, -, ,, ?
Month1-12 or JAN-DEC*, /, -, ,
Day of week0-6 or SUN-SAT*, /, -, ,, ?

Special characters explained

  • * — any value. * * * * * = every minute.
  • , — list. 0 9,12,18 * * * = 9 AM, noon, and 6 PM daily.
  • - — range. 0 9-17 * * 1-5 = every hour 9 AM–5 PM, weekdays.
  • / — step. */15 * * * * = every 15 minutes.
  • ? — no specific value (used in day-of-month / day-of-week to mean "use the other field").

Ready-to-use expressions

ScheduleExpression
Every minute* * * * *
Every 5 minutes*/5 * * * *
Every 15 minutes*/15 * * * *
Every hour, on the hour0 * * * *
Every 2 hours0 */2 * * *
9:30 AM every day30 9 * * *
Midnight every day0 0 * * *
3 AM every day0 3 * * *
Weekdays at 9 AM0 9 * * 1-5
Every Friday at 6 PM0 18 * * 5
Every Sunday at noon0 12 * * 0
First of every month, midnight0 0 1 * *
January 1st, midnight0 0 1 1 *
Every Monday, midnight0 0 * * 1
10:15 AM on weekdays15 10 ? * 1-5
Every hour, 9 AM–5 PM, weekdays0 9-17 * * 1-5

Mistakes that bite

1

Confusing day-of-month and day-of-week

If both fields are set to specific values, most cron engines run when either matches (OR logic, not AND). 0 0 15 * 1 runs every 15th AND every Monday — usually not what you want. Use ? in one of the two fields to disambiguate (Quartz syntax).

2

Forgetting the timezone

A cron expression is timezone-agnostic — "9 AM" depends on whose 9 AM. Linux crontab uses the server's local time. Hosted schedulers (Requex, GitHub Actions, etc.) usually default to UTC. Always set an explicit IANA timezone for daily schedules.

3

Day-of-week numbering varies

Some engines use 0–6 with Sunday = 0. Others use 1–7 with Sunday = 1. Spelled-out names (MON, TUE, ...) avoid the ambiguity.

4

Sub-minute schedules do not exist

Standard cron has 1-minute resolution. "Every 30 seconds" needs a different approach (a long-running script, or two cron jobs offset by 30 seconds via sleep).

Common questions

How do I write a cron expression for every 30 minutes?

*/30 * * * * runs at :00 and :30 of every hour. Or list the minutes explicitly: 0,30 * * * *.

How do I run a job only on the last day of the month?

Standard cron does not have an "L" (last) shortcut. Use 0 0 28-31 * * combined with a script-level check, or use Quartz cron (supported by some hosted schedulers) which adds L and W tokens.

Is @daily a real cron expression?

It is a shortcut supported by Linux cron — equivalent to 0 0 * * *. Other shortcuts: @hourly, @weekly, @monthly, @yearly. Most hosted schedulers support them; some do not, so the explicit 5-field form is safer.

Where can I run this expression?

Anywhere that accepts cron syntax — Linux crontab, GitHub Actions schedules, AWS EventBridge, Kubernetes CronJob, GitLab pipelines, and hosted schedulers like Requex's online cron job service.

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