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Cron Expression Parser

Read a 5-field cron expression in plain language and see five rough sample run times. Common patterns only; the run times are an estimate.

Paste or type your input; results appear instantly and errors are shown below the input.

Your files and input never leave your browser – nothing is uploaded.

Common presets:

Meaning / schedule:

Sample run times (estimate)

    Cron expression parser: what the sentence can say

    Look at the five sample run times below the sentence: they ignore the day, month and weekday fields. Keep that in mind while you use this cron expression parser. It turns a five-field expression into one plain sentence, and that part is exact for only a few patterns: every minute, every hour at minute 0, once a day, Monday to Friday written as 1-5, and the 1st of the month. Everything else appears as the five fields in square brackets.

    The field order is minute, hour, day of month, month, weekday. Many mistakes come from swapping the first two.

    Paste, read, compare

    1. Type or paste the line into "Cron expression (5 fields)". The field starts with 0 4 * * *.
    2. Or press one of the seven presets, for example "Monday to Friday at 08:00". The preset replaces the text.
    3. Read the sentence under "Meaning / schedule". It updates on every key press.
    4. Compare the sentence with what you meant. Fix the field that is wrong.

    A colleague leaves 30 4 * * 1-5 in a deploy file and you want to know, before you touch the crontab, if it means 04:30 on weekdays. The sentence tells you.

    Why the sample times are only rough

    The tool starts tomorrow and adds one day per row. It takes hour and minute from the first two fields, but only when a field starts with a number. Day, month and weekday play no role. So 0 8 * * 1-5 still lists five days in a row, weekend included, and 0 0 1 * * does not jump from month to month. A field such as */15 keeps the current hour or minute. The times use the clock and time zone of your device.

    Steps and lists in the minute or hour field can also give odd sentences. */5 * * * * reads "Daily at *:*/5".

    Checks the tool does not make

    Value ranges are not checked, so 99 99 * * * is accepted. Names such as MON or JAN are not read. @daily and six-field expressions with seconds are rejected with the message "Invalid number of fields".

    The text never leaves your browser. The page runs plain JavaScript, typing or pressing a preset sends no request, and the tool does not use the clipboard or create a file.

    Frequently asked questions (FAQ)

    It runs every day at 04:00. The first field is the minute (0), the second is the hour (4), and the three stars mean every day, every month, every weekday.