Cron expressions schedule the automated world: nightly backups, hourly syncs, Monday-morning reports. Five space-separated fields — minute, hour, day of month, month, day of week — encode the schedule, but their syntax (*/15, 1-5, MON-FRI) is famously hard to read back. A misread cron line can mean a backup that silently never runs.
This parser translates any cron expression into plain English and shows the next scheduled run times, so you can verify a schedule before deploying it to crontab, GitHub Actions, Kubernetes, or your CI system.
How to Use This Tool
- Paste or type a cron expression like */15 9-17 * * 1-5.
- Read the plain-English description to confirm it matches your intent.
- Check the list of upcoming run times.
- Adjust fields and re-check until the schedule is exactly right.
Frequently Asked Questions
What do the five fields mean in order?
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). An asterisk means 'every value'; */5 in the minute field means every 5 minutes.
What timezone do cron jobs run in?
Whatever the host system's timezone is — classic cron has no timezone syntax. Servers typically run in UTC, so a job scheduled for 9:00 may fire at 10:00 or 11:00 Paris time depending on daylight saving. Many outages trace back to exactly this.
What does it mean when both day-of-month and day-of-week are set?
In standard cron they combine with OR, which surprises everyone: '0 0 13 * 5' runs on the 13th of each month AND every Friday — not only on Friday the 13th. Quartz and some schedulers behave differently, so always verify with a parser.