Question 1

What is a cron expression?

Accepted Answer

A cron expression is a string that defines a schedule for running tasks. Unix cron uses 5 fields: minute, hour, day of month, month, and day of week. For example, 0 9 * * 1-5 means every weekday at 9:00 AM.

Question 2

How do I run a cron job every 5 minutes?

Accepted Answer

Use */5 * * * * to run a command every 5 minutes. The */5 in the minute field means 'every 5th value'.

Question 3

What is the difference between Unix cron and Quartz cron?

Accepted Answer

Unix cron uses 5 fields (minute, hour, day, month, weekday). Quartz cron uses 6-7 fields, adding seconds and an optional year field. Quartz also uses ? instead of * for day-of-month and day-of-week fields when one is unspecified.

Question 4

How do I run a cron job daily at a specific time?

Accepted Answer

Use 0 HH * * * where HH is the hour in 24-hour format. For example, 0 9 * * * runs at 9:00 AM daily, 0 17 * * * runs at 5:00 PM daily. The first field (0) is minutes, second field is the hour, and the * wildcards mean every day, every month, every weekday.

Question 5

How do I test a cron expression before deploying?

Accepted Answer

Use this generator's Preview tab to see the next 10 execution times instantly. You can also paste any expression into the validator at aicalc.cloud/cron-validator/ to check syntax across Unix, Quartz, and AWS dialects. Always test with a dry-run command before adding to crontab.

Question 6

How do I use the natural language to cron feature?

Accepted Answer

Type a phrase like 'every 5 minutes', 'weekdays at 9am', or 'daily at midnight' into the Natural Language input and click Generate. The tool converts it to a cron expression, shows the explanation, and previews the next 10 scheduled run times in UTC.

Cron Expression Generator

Natural Language

Visual Builder

Next 10 executions (UTC)

Common Cron Patterns

Popular Cron Schedules

Frequently Asked Questions

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