Cron schedule visualization generator

Cron Expression Builder Cron schedule generator

Quickly create Cron schedules through the graphical interface, which supports visual settings, Reverse Parse, Next Run preview and commonly used Presets. No need to manually write complex Cron Expressions.

Commonly used Presets

per minute hourly every 5 minutes every 6 hours 3 a.m. every day Weekdays 18:30 every sunday 1st of every month 1/1 per year Every 10 minutes on weekdays every 2 hours

Visual schedule setting

Minute 0–59 *

Hour 0–23 *

Day of Month 1–31 *

Month 1–12 *

Day of Week (week) 0=Sun *

Cron Expression

* * * * *

Execute every minute

✓ Correct format

Next Run Preview

Calculated based on current time

After setting the schedule, the next 5 execution times will be displayed.

Reverse Parse — paste Cron parse

Frequently Asked Questions (FAQ)

What is Cron Expression?

Cron Expression (Cron expression) is a string format used to describe the execution time of scheduled tasks. It is widely used in systems such as Linux Crontab, Kubernetes CronJob, and GitHub Actions. The standard 5-column format is:

分時日月星期

Each field can be a number,*(optional),,(list),-(range),/(stepping).

What is the difference between five-column and six-column Cron?

Standard Linux Crontab uses 5 fields:分時日月星期. Some applications (such as some Java Quartz Schedulers) support 6 columns, adding at the beginning 秒：秒分時日月星期. This tool uses the standard 5-column format that is common to Linux Crontab and Kubernetes CronJobs.

What do the special symbols * and - / represent respectively?

• * (asterisk): means "every", such as every day, every hour
• , (comma): list, such as 1,3,5 Represents the 1st, 3rd, and 5th
• - (minus sign): range, such as 1-5 Represents 1 to 5
• / (slash): step, such as */5 means every 5 units
These symbols can be used in combination, e.g. */15 9-17 * * 1-5 Indicates that it is executed every 15 minutes between 9:00 and 17:00 from Monday to Friday.

How to use Crontab in Linux?

Use crontab -e Edit the current user's Crontab file. One task per line, the format is:

0 3 * * * /usr/bin/backup.sh

Use crontab -l List current tasks,crontab -r Delete all tasks. in crontab % If you need to escape, it is recommended to write the script into a .sh file before executing it.

Is the Cron format of Kubernetes CronJob the same as Linux?

Basically the same. Kubernetes CronJob uses the same 5-field format, but with one important difference: Kubernetes uses UTC time (instead of system Localtime) and requires that fields cannot use non-standard aliases (such as @yearly). Additionally, Kubernetes CronJob supports timeZone Field specifies time zone (needs to be enabled CronJobTimeZone function gate).

Example Kubernetes CronJob YAML:

spec:
  schedule: "0 3 * * *"
  timeZone: "Asia/Taipei"
  jobTemplate:
    spec:
      template:
        spec:
          containers:
          name: hello

Is Sunday in Cron 0 or 7?

Both are fine. In standard Cron, the Day of Week field accepts 0 or 7 Indicates Sunday. Some implementations (such as Quartz Scheduler) use 1(Monday) to 7(Sunday). This tool uses standard Linux Crontab conventions:0 for Sunday,1-6 For Monday to Saturday.

How do I verify that my cron schedule is correct?

This tool provides three verification methods:
• Instant Human Readable: Display human-readable description text immediately after generation
• Next Run Preview: Displays the actual execution times of the next 5 times to help confirm whether the schedule meets expectations.
• Format validation: Automatically check whether the field value is out of range and whether the special symbols are used correctly.
It is recommended to check the Next Run preview after creating the schedule to ensure that the execution time is correct before deploying.

Complete tutorial on Cron scheduling

What is Cron?

Cron is a scheduled task scheduling tool in Linux/Unix systems. Its name comes from the Greek word Chronos (time). Cron runs as a background service (daemon) and automatically executes specified commands or scripts according to the time rules in the configuration file (Crontab).

Cron has applications far beyond Linux system management:

Linux Crontab — System backup, log rotation, system update
Kubernetes CronJob — Scheduled tasks in a containerized environment
GitHub Actions — Scheduled triggering of CI/CD pipelines
NAS system — Data synchronization, snapshot scheduling
Database maintenance — Regular backup and index rebuilding
Monitor alarms — Regular health checks and indicator collection

Cron Expression field description

field	scope	Description
Minute	0–59	minutes in hour
Hour	0–23	hours in a day
Day of Month	1–31	day of month
Month	1–12	month in year
Day of Week	0–7	Day of the week (0,7=day, 1=monday…6=saturday)

Practical application examples

0 3 * * *

Database backup is performed every day at 3 am

*/5 * * * *

Perform website health checks every 5 minutes

0 */6 * * *

Synchronize data to backup site every 6 hours

30 4 1 * *

Generate monthly report at 4:30 on the 1st of every month

0 22 * * 5

Releases deployed every Friday at 10pm

0 0 1 1 *

Annual statistics reset to zero on January 1 every year