This free online cron expression parser converts cron syntax into plain English descriptions and shows you the next 5 scheduled run times. Whether you're debugging a crontab entry, setting up CI/CD pipeline schedules, or configuring serverless function triggers, this cron schedule calculator gives you instant clarity on exactly when your jobs will execute.
Step-by-Step
Enter a cron expression — Type or paste a standard 5-field cron expression (minute, hour, day-of-month, month, day-of-week) into the input field.
Read the description — The tool instantly translates the expression into a human-readable English sentence like "Every weekday at 9:30 AM".
View upcoming runs — See the next 5 scheduled execution times with dates and times in your local timezone.
Try presets — Click preset buttons for common schedules like "Every minute", "Daily at midnight", "Every Monday at 9 AM", etc.
Features
Human-readable descriptions — Translates complex cron syntax into clear English sentences that anyone can understand.
Next 5 run times — Shows exactly when the expression will trigger next, accounting for the current date and time.
Visual field breakdown — Each of the 5 cron fields is labeled and explained individually.
Preset schedules — Common schedules available as one-click presets.
Validation — Invalid expressions are flagged with specific error messages.
Local timezone — Run times are displayed in your browser's timezone.
100% client-side — All parsing and calculation happens in your browser.
Common Use Cases
Crontab Debugging — Paste cron expressions from your server's crontab to verify they fire at the intended times. No more guessing whether 0 */2 * * 1-5 means every 2 hours on weekdays.
CI/CD Pipeline Schedules — Verify GitHub Actions, GitLab CI, and Jenkins cron-triggered schedules before committing them to your pipeline configuration.
Serverless Function Timers — AWS Lambda (EventBridge), Google Cloud Functions, and Azure Functions all use cron expressions for scheduled triggers. Validate them here first.
Database Maintenance Windows — Confirm that backup, vacuum, and reindex schedules are set correctly before deploying database maintenance jobs.
Monitoring and Alerting — Verify cron schedules for health checks, uptime monitors, and automated alert reporting.
- Use */5 for "every 5" intervals, 1,15 for specific values, and 1-5 for ranges.
- 0 9 * * 1-5 = weekdays at 9:00 AM. 0 0 1 * * = first day of every month at midnight.
- Remember that cron uses a 24-hour clock. 14 in the hour field means 2:00 PM.
- Some systems (like AWS EventBridge) use 6-field cron with a seconds field — this tool uses the standard 5-field format.
Why Use This Tool?
Cron expressions are notoriously hard to read and easy to get wrong. A single misplaced asterisk can make a job run every minute instead of every hour. This parser eliminates guesswork by showing you exactly what the expression means and when it will run. All computation happens in your browser — no server calls, no data collection. It's the fastest way to validate cron schedules during development and deployment.