Dates & Scheduling
Cron Expression Builder
Describe when a task should run and get a ready-to-copy cron expression, with a plain-language summary and the next run times. Nothing leaves your browser.
Schedule
build visuallyCron expression
live0 9 * * *
Advanced — edit manually
optional
Field order: minute hour day of month
month day of week. Supports *,
,, -, /, month and day names, and macros like
@daily. Typing here switches to a custom expression.
How it works
Your choices are turned into a standard five-field cron expression in the browser — nothing is uploaded. The summary and next run times follow Vixie cron semantics: when both day-of-month and day-of-week are restricted, the schedule matches either field. Upcoming runs are calculated in your device’s local time zone.
Practical uses
Build a standard five-field cron expression from a scheduling intent, show a plain-language summary and the next run times, and copy the expression.
Common ways to use it
- Produce a crontab line for a recurring job without remembering the field order.
- Check a schedule in plain language before pasting it into a server config.
- Preview the next runs of the expression you just built.
Weekdays at 09:00
Input
Mode: Weekly Time: 09:00 Days: Mon Tue Wed Thu Fri
Output
Expression: 0 9 * * 1,2,3,4,5 Summary: At 09:00 (9:00 AM) on Monday through Friday. Next runs: Thu, 1 Jan 2026 09:00 (9:00 AM) Fri, 2 Jan 2026 09:00 (9:00 AM) Mon, 5 Jan 2026 09:00 (9:00 AM)
Verified with the tool's buildExpression, parseCron and nextRuns functions from a reference time of 2026-01-01 07:30. The field order is minute hour day-of-month month day-of-week.
Options that matter
- Frequency — every N minutes, every N hours, daily, weekly, monthly, yearly, or custom.
- Time — the hour and minute used by the daily, weekly, monthly and yearly modes.
- Days / day of month / month — restrict a weekly, monthly or yearly schedule.
- Custom expression — type any five-field expression using *, comma, dash, slash, month and day names, or macros such as @daily.
- Minutes interval and hours interval — sliders clamped to 1–59 and 1–23 respectively.
Things to keep in mind
- Standard five-field cron only; an expression with a seconds field (six fields) is not accepted.
- The summary and next runs follow Vixie cron semantics: when both day-of-month and day-of-week are restricted, a match on either field counts.
- Next runs are computed in the device local time zone; this tool has no time-zone selector.
- Values are range-checked, so a minute of 60, a month of 13, or a step of 0 is rejected with an error.