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Cron Expression Parser

Parse and explain cron expressions in plain English. See the next scheduled run times for any cron schedule.

Features

  • Parse any standard 5-field cron expression instantly
  • Get a human-readable explanation in plain English
  • See the next 5 scheduled run times from now
  • View a breakdown of each cron field with its meaning
  • Quick-click presets for common schedules
  • Works offline — your expressions never leave your browser

How to Use

  1. 1Enter a cron expression in the input field (e.g., */15 * * * *)
  2. 2Or click a preset button to load a common schedule
  3. 3Read the plain-English description of what the expression does
  4. 4Review the field-by-field breakdown table
  5. 5Check the next 5 scheduled run times

Examples

Every 15 minutes

Input

*/15 * * * *

Output

Every 15 minutes
Daily at 3:30 AM

Input

30 3 * * *

Output

At 3:30 AM
Weekdays at 9 AM

Input

0 9 * * 1-5

Output

At 9:00 AM, on Monday through Friday
Monthly on the 1st at midnight

Input

0 0 1 * *

Output

At 12:00 AM, on day 1 of the month

What is a Cron Expression?

A cron expression is a string of five fields separated by spaces that defines a schedule for recurring tasks. Originally part of Unix-like operating systems, cron is now used everywhere — from Linux servers and CI/CD pipelines to cloud schedulers like AWS CloudWatch, Google Cloud Scheduler, and Kubernetes CronJobs.

Each of the five fields represents a time unit: minute (0–59), hour (0–23), day of the month (1–31), month (1–12), and day of the week (0–6, where 0 is Sunday). A wildcard (*) means "every possible value," a slash (/) defines a step interval, a dash (-) defines a range, and a comma (,) separates a list of specific values.

For example, the expression "30 3 * * *" means "at minute 30 of hour 3, every day, every month, every weekday" — in plain English, "every day at 3:30 AM." The expression "0 9 * * 1-5" means "at 9:00 AM, Monday through Friday." These compact strings pack a lot of scheduling power into very few characters.

Parsing cron expressions by hand is error-prone, especially with complex combinations of ranges, steps, and lists. A cron parser translates the expression into a human-readable description and calculates the next execution times, so you can verify your schedule before deploying it. This avoids costly mistakes like a backup job running every minute instead of every hour.

This tool supports the standard five-field cron format used by crontab, systemd timers, and most scheduling libraries. It accepts numeric values, ranges (1-5), steps (*/10), lists (1,3,5), and month/weekday names (MON, JAN). Paste any expression and instantly see what it does and when it will run next.

Frequently Asked Questions

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