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Cron expression parser

plain English · field breakdown · next runs in any time zone

Type or paste a cron expression. The parser explains it in a sentence, shows what each field means, and lists the next times it fires in the time zone you pick — with daylight-saving gaps flagged instead of silently skipped.

How to use the cron parser

1. Type or paste an expression into the box. It is read as you type; there is no Run button.
2. Check the Dialect. Unix cron is the default. Paste an AWS cron(…), a six-field Quartz or Spring expression or a Jenkins H spec and the dialect switches to match.
3. Pick the Time zone the scheduler runs in. The run list shows that zone's wall-clock time and the same moment in UTC.
4. Read the sentence at the top, then the per-field breakdown underneath it. Warnings about things that are legal but probably wrong — * 9 * * * running sixty times, an uneven */7 — appear under the fields.
5. Use Copy link to share the exact expression, dialect and zone; the link opens this page with them filled in.

What the five fields mean

Quartz and Spring put a seconds field in front, Quartz allows a trailing year, and AWS EventBridge requires the year. The cron cheat sheet lays the dialects side by side.

The rule that surprises everyone: day-of-month OR day-of-week

In Linux cron, when both day fields are restricted the job runs when either matches. 0 0 1 * 1 runs on the 1st of every month and on every Monday, not only on Mondays that fall on the 1st. The exception is a field that starts with *: 0 0 */2 * 1 is read as "odd-numbered days that are also Mondays". Kubernetes counts only a bare * as unrestricted, so the same string means something else there, and Jenkins, Spring and Azure always require both. The parser applies the rule of the dialect you select and says which one it used.

FAQ

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