QQuickKit

Cron Expression Parser

Parse standard 5-field cron expressions into a human-readable schedule description and see the next 5 upcoming run times.

About This Tool

Cron is the standard syntax for scheduling recurring tasks on Unix-like systems, made up of 5 space-separated fields: minute, hour, day of month, month and day of week. Because the field order is easy to mix up and wildcard/step syntax (like */15) isn't always intuitive, developers often need a quick way to double-check a schedule. QuickKit's Cron Expression Parser breaks each field down into a readable description and computes the next 5 actual run times, so you can verify a schedule before deploying it.

Features

  • ✓Standard 5-Field Parsing — Fully parses the minute, hour, day-of-month, month and day-of-week fields.
  • ✓Field Syntax Support — Supports wildcards (*), comma lists (,), ranges (-) and step values (/) in any combination.
  • ✓Per-Field Breakdown — Translates each field into a plain-language description, showing weekday and month names instead of raw numbers.
  • ✓Next Run Prediction — Calculates and lists the next 5 actual run times based on the current time.
  • ✓Clear Error Messages — Pinpoints exactly which field is wrong when the field count or a value is invalid.

FAQ

What do the 5 fields in a cron expression mean?
From left to right: minute (0-59), hour (0-23), day of month (1-31), month (1-12), day of week (0-6, where 0 is Sunday). For example, 0 9 * * 1-5 means "every weekday at 9:00 AM".
Why does specifying both day-of-month and day-of-week give unexpected results?
This is standard cron behavior: when both the day-of-month and day-of-week fields are restricted (not *), the schedule fires if either condition matches (OR logic), not both (AND logic). This tool's next-run prediction follows that standard rule.
Does this tool support shorthand syntax like @daily or @hourly?
Not currently. This tool only parses standard 5-field POSIX cron syntax. If your scheduler uses shorthand (like crontab's @daily), convert it to the equivalent 5-field expression first (@daily is equivalent to 0 0 * * *).
What timezone are the next run times calculated in?
This tool calculates and displays times in your browser's local timezone. If your server or scheduler runs cron jobs in UTC or another timezone, account for the difference when comparing.

Further Reading