Cron Expression Explainer
Runs in your browser, nothing is uploaded. Your input is saved in the page link.Explain a cron expression in plain English and preview its next run times. Supports standard, Spring, and Quartz syntax.
About this tool
Paste a cron expression to see what it means in plain English, how each field is read, and when it will run next. The format is detected from the number of fields: 5 for standard Unix cron, 6 for Spring and Quartz (seconds first), and 7 for Quartz with a year. The 6- and 7-field formats also understand ?, L, W, and #. Shortcuts such as @daily and @hourly work too.
Questions
Which formats are supported?
Standard cron with 5 fields (minute, hour, day-of-month, month, day-of-week), plus the 6-field form used by Spring’s @Scheduled and Quartz, which adds a seconds field first, and the 7-field Quartz form with a trailing year. Month and weekday names such as JAN and MON-FRI work in every format.
What happens when both day-of-month and day-of-week are set?
In standard cron the job runs when either one matches, unless one of them starts with *, in which case both must match. This is a famous source of surprises. In the 6- and 7-field formats this tool requires both to match, and Quartz rejects the combination unless one field is ?.
Why are my run times different from my server?
Cron runs in the scheduler’s time zone, which is often UTC on servers and containers. Use the UTC and Local switch to compare. In Spring you can set the zone on @Scheduled, and Quartz uses the trigger’s time zone. Local times skipped by a daylight-saving jump are left out.
Does 0 mean Sunday or Monday?
This tool follows standard cron, where 0 and 7 are both Sunday. Not every scheduler agrees: Quartz counts Sunday as 1. Using names such as MON-FRI avoids the problem.
Why does */45 not run every 45 minutes?
Steps count from the start of the field’s range, not from the last run. */45 in the minute field runs at minute 0 and minute 45 of every hour, so the gap alternates between 45 and 15 minutes.