CRON Job Schedule Parser
Parse CRON expressions into human-readable format
CRON Expression Parser
Parse and understand CRON job schedules
Format: minute hour day month day-of-week
Examples
CRON Format
Privacy & Security
All CRON parsing and generation happens entirely in your browser using JavaScript. Your CRON expressions are never uploaded to our servers, transmitted over the network, stored in databases, or logged anywhere. When you close the page, your expressions are permanently erased from browser memory. Completely private and secure.
About CRON Parser
Parse and understand CRON expressions with our free online CRON parser and translator. Whether you're a DevOps engineer scheduling automated tasks, a backend developer implementing job queues, a system administrator managing server maintenance, or a student learning UNIX scheduling, our tool instantly converts cryptic CRON syntax into plain English explanations. Perfect for understanding inherited crontab files, debugging scheduling issues, and generating correct CRON expressions without memorizing complex syntax rules or consulting documentation repeatedly.
Key Features
Human-Readable Translation
Convert CRON expressions to plain English descriptions instantly
Next Run Time Calculation
See the next 10 execution times for your scheduled job with dates and times
Syntax Validation
Validate CRON expressions and identify syntax errors with helpful error messages
Visual Schedule Calendar
View scheduled execution times on an interactive calendar display
CRON Expression Generator
Build CRON expressions using dropdowns and form inputs without memorizing syntax
Common Patterns Library
Quick-select common schedules like daily, weekly, monthly, or hourly
Timezone Support
Calculate execution times in different timezones for distributed systems
Five & Six Field Support
Parse standard 5-field and extended 6-field CRON syntax (with seconds)
Special Characters
Understand *, -, /, ?, L, W, # and other special CRON characters
Copy & Export
Copy generated CRON expressions or human descriptions to clipboard instantly
How to Use the CRON Parser
Enter CRON Expression
Paste your CRON expression (e.g., '0 9 * * 1-5') into the input field
View Human Description
See the plain English translation explaining when the job runs (e.g., 'At 9:00 AM, Monday through Friday')
Check Next Runs
Review the next scheduled execution times to verify the schedule is correct
Generate or Copy
Generate CRON expressions using the builder or copy the expression for your crontab
Frequently Asked Questions
What is a CRON expression and how does it work?
A CRON expression is a string of 5 or 6 fields (seconds, minute, hour, day of month, month, day of week) that defines a schedule for running automated tasks. Each field can contain numbers, ranges (1-5), lists (1,3,5), wildcards (*), or special characters. For example, '0 9 * * 1-5' means 'at 9:00 AM on weekdays'. CRON originated in Unix systems but is now used in many platforms and programming languages.
What do the five fields in a CRON expression mean?
Standard CRON has five fields: Minute (0-59), Hour (0-23), Day of Month (1-31), Month (1-12), and Day of Week (0-6, Sunday=0). Some systems support a sixth field for Seconds (0-59). For example, '30 14 1 * *' means 'At 2:30 PM on the first day of every month'.
What do special characters like *, /, and - mean in CRON?
CRON special characters: * (asterisk) means 'every' (e.g., * in hour = every hour), - (dash) defines ranges (e.g., 1-5 = Monday through Friday), / (slash) defines step values (e.g., */15 = every 15 minutes), , (comma) separates list items (e.g., 1,3,5), ? (question mark) means 'no specific value' for day fields, and L means 'last' (last day of month or week).
Why do some CRON expressions have 6 fields instead of 5?
Extended CRON syntax includes a seconds field as the first field, giving you second-level precision. This is supported by some modern CRON implementations and libraries (like Spring Scheduler or Quartz) but not traditional Unix crontab. The format is: second, minute, hour, day, month, day-of-week.
How do I schedule a job to run every day at midnight?
Use '0 0 * * *' for every day at midnight (00:00). The first 0 is minute, second 0 is hour (midnight), and the three asterisks mean every day of the month, every month, every day of the week.
Is this CRON parser free?
Yes! Our CRON parser is completely free to use with unlimited parsing and generation, no registration required.
Does it support all CRON syntax variations?
Yes! The parser supports standard Unix crontab syntax, extended 6-field format with seconds, special characters (*, -, /, ?, L, W, #), and common extensions used by various CRON implementations across different platforms and programming languages.
Will my CRON expressions be stored anywhere?
No. All CRON parsing happens entirely in your browser using JavaScript. Your expressions are never uploaded to our servers, stored in databases, or transmitted anywhere. Completely private and secure.
Common Use Cases
- Crontab Management: Understand and edit crontab files on Linux servers without memorizing syntax
- CI/CD Pipeline Scheduling: Configure scheduled builds and deployments in Jenkins, GitLab CI, or GitHub Actions
- Database Backups: Schedule automated database backup scripts at specific times and intervals
- Job Queue Configuration: Set up recurring jobs in Node-cron, APScheduler, or Celery Beat
- Maintenance Windows: Plan server maintenance, updates, and cleanup tasks during off-peak hours
- Report Generation: Schedule automated report generation and email delivery at specific times
- Data Synchronization: Configure periodic data syncs between systems, APIs, and databases
- Monitoring & Alerts: Set up scheduled health checks, system monitoring, and alerting jobs
Why Use Our CRON Parser?
CRON expressions are powerful but notoriously cryptic - even experienced developers struggle to read expressions like '0 0 1,15 * *' at a glance or remember if Sunday is 0 or 7. Misreading CRON syntax can cause jobs to run at the wrong time, miss critical maintenance windows, or execute far more frequently than intended. Our free CRON parser eliminates guesswork by instantly translating expressions to plain English and showing exact execution times. Whether you're inheriting a crontab file from a previous developer, debugging why a job isn't running when expected, or just trying to schedule a simple weekly backup, you'll appreciate the instant translation, next run time preview, and expression generator. No more consulting documentation or manually calculating schedules - just parse and understand immediately.