Cron Expression Builder

A cron expression is a compact string of five fields that tells a scheduler when to run a job — used in Linux crontab, GitHub Actions, cloud functions, CI/CD pipelines, and countless other systems. The standard format is minute, hour, day-of-month, month, and day-of-week, and each field accepts wildcards, step values, ranges, and lists. This tool lets you build any expression visually by editing those five fields and immediately see an accurate plain-English description of when the job will fire.

You can also paste an existing cron expression into the raw input and click Parse to populate the fields automatically and read the description. Preset buttons cover the most common schedules — every minute, hourly, daily at midnight, weekly on Monday, and monthly on the first — so you can start from a known-good expression and tweak from there. Everything runs locally; no data is sent to any server.