Quick Answer
Cron schedules recurring tasks on Linux using five time fields — minute, hour, day-of-month, month, and weekday — followed by the command to run. A single misplaced asterisk or off-by-one hour value runs your backup at the wrong time or not at all, with no error output from the cron daemon itself. Expressing `0 2 * * 1-5` as weekdays at 2am is easy to misread when you are editing crontab at midnight during an incident. This builder translates your selections into a valid five-field expression and shows a live human-readable summary so you can confirm the schedule before pasting into `crontab -e`. Pick presets for every five minutes, hourly, daily, weekly, or monthly runs, or switch to Custom to set each field. The output includes the full crontab line ready to copy. Works in any modern browser with JavaScript enabled. Pair it with disk monitoring or backup scripts, then schedule them with a line you have visually verified instead of guessing field order from man pages.
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6 scripts + shared library + 52-page field guide. The production layer the free snippets don't cover.
Get the Toolkit →How do I run a cron job every 5 minutes?
Set the minute field to `*/5` and leave the other fields as `*`. The resulting crontab line is `*/5 * * * * /path/to/command`. The builder generates this automatically when you select the "Every 5 minutes" preset.
What is the format for a crontab entry?
A crontab line has five time fields followed by the command: minute (0–59), hour (0–23), day of month (1–31), month (1–12), day of week (0–7, where both 0 and 7 are Sunday). Each field accepts numbers, ranges (1-5), lists (1,3,5), or step values (*/2).
How do I edit my crontab?
Run `crontab -e` in the terminal. This opens your personal crontab file in the default editor. Paste the generated line, save, and exit. The cron daemon picks up changes immediately — no restart needed.
Can I run a cron job on weekdays only?
Yes. Set the day of week field to `1-5` to run Monday through Friday. The builder supports range syntax, so you can also set it to `1,3,5` for Monday, Wednesday, and Friday only.
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0 2 * * *# Add your command above to see the full crontab entry