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About this tool
Translate any 5-field cron expression into plain English with a field-by-field breakdown and the next scheduled run times.
This explainer parses any standard 5-field crontab expression — minute, hour, day-of-month, month, day-of-week — and translates it into a plain-English sentence, a field-by-field breakdown and the next five run times in UTC. It implements the crontab(5) grammar exactly, including @macros like @daily, name tokens like MON or JAN, and Vixie cron's either/or rule when both day fields are restricted, so what it says matches what your cron daemon will actually do.
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Implements the crontab(5) grammar including steps, ranges, lists, names and 7-as-Sunday.
Shows the next five occurrences in UTC computed from any start time you choose.
When both day-of-month and day-of-week are set, the schedule matches either — exactly like Vixie cron.
In order: minute (0-59), hour (0-23), day-of-month (1-31), month (1-12 or JAN-DEC) and day-of-week (0-7 or SUN-SAT, where both 0 and 7 mean Sunday). Each field takes a value, a range like 9-17, a step like */15, or a comma-separated list, and an asterisk means every allowed value.
The job runs when either field matches, not both — this is the rule from crontab(5) that surprises most people. So 0 12 15 * 3 runs at noon on the 15th of every month and on every Wednesday, which is why a job restricted to "the 15th" can also fire mid-week.
It means every 15th value across the field's full range — in the minute field, minutes 0, 15, 30 and 45. A step can also apply to a range: 9-17/2 in the hour field matches 9, 11, 13, 15 and 17, and a bare value with a step like 5/10 means from 5 to the maximum in steps of 10.
Classic cron daemons evaluate expressions in the server's local timezone, not UTC, though many modern runners (Kubernetes CronJobs by default, most CI schedulers) use UTC. This tool predicts run times in UTC; if your server runs in another timezone, shift the predictions by that offset or set CRON_TZ where your cron implementation supports it.