Cron Expression Builder
Build and validate cron expressions visually. Get a human-readable description of your schedule and preview the next 5 run times. Runs entirely in your browser.
Frequently Asked Questions
What is a cron expression?
A cron expression is a string of five fields (minute, hour, day of month, month, day of week) that define a recurring schedule. For example, "0 9 * * 1-5" means "9:00 AM every weekday".
Are the next run times shown in UTC or local time?
Run times are shown in your local browser timezone.
Does this support non-standard fields like seconds or years?
No — this tool uses the standard five-field Unix cron format. Seconds and year fields used by some schedulers (like Spring or AWS EventBridge) are not supported here.
Is my data private?
Yes — completely. Everything runs locally in your browser. Nothing is sent to any server, and nothing is retained after you close the tab.