cron-parser-cli

Parse and explain cron expressions from the command line — no external dependencies.

Installation

npm install -g cron-parser-cli

Usage

Explain a cron expression

cron-parse "*/5 * * * *"
#  Expression : */5 * * * *
#  Meaning    : Every 5 minutes

cron-parse "0 9 * * 1-5"
#  Expression : 0 9 * * 1-5
#  Meaning    : At 9:00 AM, Monday through Friday

cron-parse "30 8 1 * *"
#  Expression : 30 8 1 * *
#  Meaning    : At 8:30 AM, day 1 of the month

Show next 5 execution times

cron-parse --next "0 * * * *"
#  Expression : 0 * * * *
#  Meaning    : Every hour (at :00)
#
#  Next 5 executions:
#    1. Mon, Mar 22 2026  15:00
#    2. Mon, Mar 22 2026  16:00
#    3. Mon, Mar 22 2026  17:00
#    4. Mon, Mar 22 2026  18:00
#    5. Mon, Mar 22 2026  19:00

Validate an expression

cron-parse --validate "*/5 * * * *"
#  Valid cron expression: "*/5 * * * *"

cron-parse --validate "99 * * * *"
#  Invalid cron expression: "99 * * * *"
#  Reason: Value "99" out of bounds [0-59] for minute

List common patterns

cron-parse --list
# Common Cron Patterns:
#   * * * * *        Every minute
#   */5 * * * *      Every 5 minutes
#   0 * * * *        Every hour (at :00)
#   0 0 * * *        Daily at midnight
#   0 9 * * 1-5      Weekdays at 9:00 AM
#   ...

Cron Format

┌──────────── minute (0-59)
│ ┌────────── hour (0-23)
│ │ ┌──────── day of month (1-31)
│ │ │ ┌────── month (1-12 or jan-dec)
│ │ │ │ ┌──── day of week (0-6 or sun-sat)
│ │ │ │ │
* * * * *

Special syntax

| Syntax | Meaning | Example | |---------|----------------------------------|------------------| | * | Any value (wildcard) | * | | */n | Every n units | */5 → every 5 | | a-b | Range from a to b | 1-5 | | a,b,c | List of values | 1,3,5 | | a-b/n | Range with step | 0-12/2 |

Month and day-of-week also accept name abbreviations: jan, feb, mon, tue, etc.

License

MIT — Wilson Xu