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Cron Expression Editor

Edit and explain five-field Unix cron expressions directly.

Processed locally in your browser

Cron expression

Five-field Unix syntax

Presets
Minuteminute 0–59
Hourhour 0–23
Day of monthday (month) 1–31
Monthmonth 1–12
Day of weekweekday 0–7

About this tool

Edit a conventional five-field Unix cron expression directly. Validation and the readable summary update locally as you type; nothing is uploaded.

How to use it

  1. Enter the minute, hour, day of month, month, and weekday fields in order, or start from a preset.
  2. Review the live description or correct the field-specific validation message.
  3. Copy the normalized expression into a compatible Unix crontab or scheduler.

Operators

  • Use * for every value, commas for lists, a hyphen for an inclusive ascending range, and /N for steps.
  • Steps may follow a wildcard or range, such as */15 or 9-17/2. Seconds fields, commands, @macros, wraparound ranges, and Quartz tokens (?, L, W, and #) are not supported.

Field bounds and names

  • Minute: 0–59; hour: 0–23; day of month: 1–31; month: 1–12; weekday: 0–7.
  • Months also accept JAN–DEC and weekdays accept SUN–SAT, case-insensitively. Both 0 and 7 represent Sunday.

Timezone ownership

  • The target server, scheduler, or cron daemon controls the execution timezone. A five-field expression does not contain timezone information.

Unix day-field semantics

  • Vixie-style cron checks how each day field begins: it uses AND when either field starts with *, including a leading wildcard step such as */2, and otherwise uses OR. A day field that effectively covers every day does not add a restriction.

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