Cron Expression Generator
Build, validate and preview cron schedules with live next-run times
Next 5 runs
Everything runs in your browser — your schedule stays on your device.
Describe the schedule, then verify it
- 1
Pick a preset or edit the five fields directly; the human-readable sentence updates as you type.
- 2
Copy the line into crontab -e, and check the next-run preview to confirm it means what you think.
What this generator emits — and why
- Plain five-field crontab (minute hour day month weekday) — the lowest common denominator that works on every Unix cron, not vendor extensions.
- Weekday accepts both 0 and 7 for Sunday because real crons disagree; steps like
*/15are used instead of@daily-style macros for portability. - The expression itself carries no time zone — it runs in whatever zone the daemon uses, which is why the next-runs preview below pins one explicitly.
Five fields, and the dialects behind them
Next runs, not just syntax
Beyond validation, the tool computes your next five actual run times from your clock — so "0 3 * * 1" becomes real Monday dates you can trust in production.
Presets for the common cases
Every minute, hourly, daily at 9am, weekly, monthly, yearly and more are one click — then the generated expression is yours to tweak.
Private and instant
Everything — validation and next-run math — runs in your browser; no schedule leaves your machine and no account or login is needed.
Frequently asked questions
What do the five fields mean?⌄
minute (0-59), hour (0-23), day-of-month (1-31), month (1-12) and day-of-week (0-6, 0=Sunday). Each field accepts a single value, a list (1,2,3), a range (1-5), a step (*/5) or combinations.
How do day-of-month and day-of-week combine?⌄
When only one of them is set it applies directly. When both are set, the standard cron behavior applies these as an OR (matches either). The tool follows that convention and reflects it in the previewed next-run times.
Is my schedule uploaded anywhere?⌄
No. Everything runs in your browser with plain JavaScript — nothing you enter is transmitted or stored.
Why does my job fire at the wrong hour?⌄
The cron daemon’s time zone wins over yours. A server on UTC running your 09:00 expression fires at 17:00 Beijing time. Set CRON_TZ or the daemon’s TZ, then re-read the preview here before assuming the schedule is wrong.
Related tools
What is a cron expression generator?
Cron is the classic Unix scheduler, and its five-field expression of minute, hour, day of month, month and day of week now lives on in cloud schedulers, CI systems, data pipelines and web hosts. One character can move a job from Mondays to Sundays, so writing the syntax by hand is famously error-prone. This tool builds the expression from friendly presets or five per-field boxes kept in sync with the main expression line, validates every field immediately, and computes the next real firing times from your local clock so you can trust the schedule before it ever runs.
Five fields and one famous day-matching quirk
- Nine presets: every minute, hourly, daily, weekly, monthly, yearly, weekdays, every 10 minutes, and a Sunday slot
- Steps, ranges and comma lists inside any field, validated per field with the offending field named
- The Vixie day rule: with both day fields restricted, either match fires the day; a starred field defers
- Two-way sync between the five small field boxes and the full expression line
- Next five run times rendered from your own clock, with one-click copy of the finished expression
Schedules people actually build here
- Nightly backups and report jobs expressed as a daily or weekday preset before pasting into crontab
- Cloud functions, queue workers and pipeline triggers drafted and sanity-checked against real upcoming dates
- Teaching moments where seeing the next five firings explains steps and ranges better than any manual
What the preview cannot promise
Only five-field expressions are accepted, so seconds fields and named months or weekdays are rejected rather than interpreted. The search walks forward minute by minute with a five-year cap, so impossible dates return an empty preview instead of hanging the tab. Run times follow the browser local timezone, so a schedule checked here may fire at a different wall-clock hour on a server set to another zone.
Privacy: expressions and preview dates are computed on your machine alone; nothing you schedule is transmitted or logged.
Last updated · 2026-09-01