Advanced cron expression editor for AWS, Vercel & Quartz

The 7-field extended cron expression has, left to right: second, minute, hour, day-of-month, month, day-of-week, year. Each field accepts the same operators as standard cron — list (,), range (-), step (/) and wildcard (*) — plus dialect-specific modifiers.

A common 7-field expression: 0 0 12 ? * 1L * — fires at noon on the last Monday of every month, every year. Translating the modifiers: the ? in day-of-month resolves the “both fields restricted” conflict; 1L in day-of-week is “last Monday”; the trailing * is “every year”.

AWS EventBridge requires 6 fields wrapped in cron(...): minute, hour, day-of-month, month, day-of-week, year. The big rule: you can specify either day-of-month or day-of-week as a value, but not both. Use ? in the field you don't want to constrain.

Example schedules:

• Every weekday at 17:00 UTC: cron(0 17 ? * MON-FRI *)
• Last day of every month at midnight UTC: cron(0 0 L * ? *)
• Every 15 minutes: cron(0/15 * * * ? *)

AWS EventBridge runs in UTC. Set a timezone in the schedule expression for non-UTC schedules — see the AWS cron guide for the full reference.

Vercel cron jobs use the standard 5-field cron syntax declared inside vercel.json:

{
  "crons": [
    { "path": "/api/cron/daily", "schedule": "0 9 * * *" },
    { "path": "/api/cron/weekly", "schedule": "0 9 * * 1" }
  ]
}

The schedule is evaluated in UTC. Hobby plan caps the frequency at once per day; Pro and Enterprise allow tighter schedules. The route under path receives a POST with a verification header on each cron tick. See the Vercel cron guide for end-to-end setup.

Quartz uses 6 or 7 fields: seconds (0-59), minute, hour, day-of-month, month, day-of-week, optional year. Day-of-week values are 1-7 (1=Sunday, 7=Saturday) or SUN-SAT — note this is one off from Unix cron. Quartz supports L, W, #, ? and forbids both day fields being values.

Example: 0 0 12 L * ? fires at noon on the last day of every month. See the full Quartz reference for all modifier semantics.

Standard cron is enough for: every-minute, every-N-minutes, hourly, daily-at-time, weekly, simple monthly. Extended cron buys you four things:

• Sub-minute precision — the seconds field.
• Last-day semantics — L for end-of-month / end-of-week.
• Nth weekday — 2#3 for “3rd Monday”.
• Year scoping — fire only in 2026, etc.

If you don't need any of those, stick with the 5-field form — it works everywhere. If you do, lean on the dialect that matches your runtime (Quartz for Java/Kotlin, robfig for Go, EventBridge for AWS, etc.).