Cron Expression Generator & Parser
Build cron expressions visually or paste existing ones to decode them. See the next execution times and get human-readable descriptions.
Quick Presets
Generated Expression
* * * * *
Every minute
Next 5 Executions
Cron Syntax Reference
| Symbol | Meaning | Example |
|---|---|---|
| * | Any value | * (every minute) |
| */n | Every n units | */15 (every 15 min) |
| n | Specific value | 30 (at minute 30) |
| a,b | Multiple values | 1,15 (1st and 15th) |
| a-b | Range | 1-5 (Mon to Fri) |
Automate your incident response
Reduce MTTR by 90% with AI-powered root cause analysis. Free to start.
Cron Expressions Explained
Cron is a time-based job scheduling system originally built for Unix operating systems. The name comes from the Greek word "chronos" (time). A cron expression defines when a job should run using five fields that specify the minute, hour, day of month, month, and day of week.
In modern DevOps, cron expressions are used far beyond simple Unix cron jobs. They schedule Kubernetes CronJobs, GitHub Actions workflows, monitoring checks, database backups, log rotation, and alert evaluations. Understanding cron syntax is an essential skill for any SRE or DevOps engineer.
Common Cron Patterns for SRE
SRE teams commonly use cron expressions for: health checks (every 1-5 minutes), metric aggregation (every 15 minutes), log cleanup (daily at low-traffic hours), certificate rotation checks (weekly), capacity reports (monthly), and SLA reports (quarterly). The key is choosing frequencies that balance freshness with system load.
Automate Monitoring with Uptimes.ai
Instead of manually scheduling monitoring checks with cron, Uptimes.ai provides continuous automated monitoring with AI-powered alerting. Our platform polls your Datadog and Prometheus metrics, correlates alerts across services, and automatically investigates incidents when they occur.