What are the five cron fields?

In order they are minute (0-59), hour (0-23), day of month (1-31), month (1-12), and day of week (0-6, where 0 is Sunday). An asterisk means every value.

What does a step value like */5 mean?

A step runs at every Nth value. */5 in the minute field means every five minutes. 0 */2 in minute and hour means every two hours on the hour.

How do ranges and lists work?

A range like 1-5 in the weekday field means Monday through Friday. A list like 0,30 in the minute field means at minute 0 and minute 30 of each hour.

What happens if both day-of-month and weekday are set?

In standard cron, when both fields are restricted the job runs when either condition matches, not both. The builder notes this behavior in its explanation.

Does this use UTC or local time?

Cron evaluates against the system or scheduler time zone, which is often UTC on servers. Confirm your platform's time zone, since the same expression fires at different wall-clock times depending on it.

Cron Expression Builder

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Cron Expression Builder

Cron is the standard syntax for scheduling recurring jobs on Unix systems, in container orchestrators, and in CI pipelines. Its five compact fields are easy to get wrong. This builder lets you set each field, applies quick presets, and translates the result into a plain-English sentence so you can confirm the schedule before shipping it.

How it works

A cron expression has five space-separated fields:

┌ minute (0-59)
│ ┌ hour (0-23)
│ │ ┌ day of month (1-31)
│ │ │ ┌ month (1-12)
│ │ │ │ ┌ day of week (0-6, Sun=0)
* * * * *

Each field accepts a single value, * for every value, a list like 0,30, a range like 1-5, or a step like */15. The builder validates each entry against its allowed range and then describes the schedule by reading the fields together, naming weekdays and months where helpful.

Tips and example

Common patterns:

*/5 * * * * — every 5 minutes.
0 9 * * 1-5 — at 09:00 on weekdays.
0 0 1 * * — at midnight on the first of every month.

Remember that when both day-of-month and day-of-week are restricted, standard cron fires if either matches. Always confirm the scheduler’s time zone, since servers frequently run in UTC and your job may fire hours away from your local expectation.