Decode a standard five-field cron expression into a readable field summary and the next scheduled run times.
Cron format
Fields are minute hour day-of-month month day-of-week, space-separated. Supports *, lists (1,3,5), ranges (1-5), and steps (*/15). Day-of-week uses 0 = Sunday through 6 = Saturday.
When to use it
Verify backup schedules, explain a production crontab to teammates, or sanity-check GitHub Actions and Kubernetes cron strings before deployment.
Limitations
Uses UTC when matching fields and listing next run times. Does not support Quartz six-field cron, named months, or L/W special characters. Very sparse schedules may require many iterations to find the next fire time.
Example
0 9 * * 1-5 runs at 09:00 on weekdays; the summary lists minute 0, hour 9, and Monday–Friday in the day-of-week field.