crontab -e

Crontab Generator

Build and verify Linux cron schedules. Instant plain-English translation and next run preview.

At 04:05.

Next 5 runs
    Presets

    Cron expression reference

    Field
    Required
    Allowed values
    Special chars
    Minute
    Yes
    0–59
    * , - /
    Hour
    Yes
    0–23
    * , - /
    Day of month
    Yes
    1–31
    * , - /
    Month
    Yes
    1–12
    * , - /
    Day of week
    Yes
    0–7 (0 or 7 = Sun)
    * , - /
    *Any value
    ,List separator: e.g. 1,3,5
    -Range: e.g. 1-5
    /Step: e.g. */15
    @yearly0 0 1 1 * (once a year)
    @monthly0 0 1 * * (once a month)
    @weekly0 0 * * 0 (once a week)
    @daily0 0 * * * (once a day)
    @hourly0 * * * * (once an hour)
    @rebootRun once on system startup

    Cron FAQ

    What is a cron expression in Linux?

    A cron expression is a five-field schedule format used by crontab in Linux to run commands automatically. The fields define minute, hour, day of month, month, and day of week.

    How do I test a crontab schedule before using it on a server?

    Use a cron schedule generator to parse the expression, read the plain-language output, and verify the next run times. This catches common mistakes before saving jobs in /etc/crontab or user crontabs.

    What is the difference between cron and crontab?

    Cron is the Linux background service that executes scheduled jobs. Crontab is the table or file format where those schedules and commands are defined.

    What does * mean in a cron expression?

    An asterisk (*) means "any value" for that field. For example, * in the minute field means every minute, and * in the day-of-week field means every day of the week.

    What is the difference between day-of-month and day-of-week fields?

    If both are set (not *), cron runs the job when EITHER condition matches. If only one is set, only that condition applies.

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