ToolVaults

Cron Expression Builder

Pick a preset or enter your own fields to build a cron expression. Includes a plain-English explainer so you know exactly when it will run.

Runs 100% in your browser — nothing is uploaded.
Presets
Fields
Expression
0 9 * * 1-5

Runs at 09:00, Monday through Friday.

How to use

  1. 1
    Pick a preset or start from scratch

    Common patterns (every minute, hourly, weekdays 9am) as one-click presets, or edit the five fields directly.

  2. 2
    Edit any field

    Minute · Hour · Day of month · Month · Day of week. Supports *, comma lists (0,15,30), ranges (1-5), and steps (*/5).

  3. 3
    Read the plain-English explainer

    The tool tells you exactly when the expression will fire so you know before you commit.

  4. 4
    Copy the expression

    Drop into crontab, GitHub Actions schedule, Cloudflare Workers cron trigger, or Kubernetes CronJob.

Examples

Every weekday at 9am
Input
Preset: weekdays 9am
Output
0 9 * * 1-5
"At 09:00, Monday through Friday"
The most common business-hours schedule.
Every 15 minutes
Input
Minute: */15 · Hour: * · rest: *
Output
*/15 * * * *
"Every 15 minutes"
For polling jobs and health checks.
First of the month at midnight
Input
Minute 0 · Hour 0 · Day 1 · Month * · Weekday *
Output
0 0 1 * *
"At 00:00 on day-of-month 1"
Monthly reports, subscription resets, cache clears.

Frequently asked

Which cron flavor does this use?

Standard 5-field UNIX cron: minute, hour, day-of-month, month, day-of-week. Cloudflare, GitHub Actions, Kubernetes CronJobs, and most Linux daemons all accept this format.

Does it support the 6-field format (with seconds)?

Not yet — the 5-field standard covers >90% of real usage. A Quartz-flavor variant with seconds is coming in a future update.

Can I paste an existing cron string?

Yes — put it in the URL as ?cron=0+9+*+*+1-5 and the fields will populate. Or type it directly into the 5 field boxes.

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