Cron Expression Parser & Explainer
Translate cron schedules into plain English and calculate upcoming execution times
MINUTE*/15
HOUR*
DAY (MONTH)*
MONTH*
DAY (WEEK)*
Human Schedule Translation:
Runs every 15 minutes of every hour, every day, of every month.
Quick Production Presets
Next Estimated Executions (UTC)
- #1Tue, 22 Sep 2026 04:49:39 GMT
- #2Tue, 22 Sep 2026 05:04:39 GMT
- #3Tue, 22 Sep 2026 05:19:39 GMT
- #4Tue, 22 Sep 2026 05:34:39 GMT
- #5Tue, 22 Sep 2026 05:49:39 GMT
Standard 5-Part Cron Syntax Reference
Cron is the ubiquitous time-based job scheduler found in Unix-like operating systems, Kubernetes CronJobs, AWS CloudWatch Events, and Celery beat. A standard cron expression consists of 5 whitespace-separated fields:
| Field | Allowed Values | Special Characters | Meaning |
|---|---|---|---|
| 1. Minute | 0 - 59 | * , - / | Exact minute of the hour |
| 2. Hour | 0 - 23 | * , - / | Hour in 24-hour format |
| 3. Day of Month | 1 - 31 | * , - / ? L W | Calendar day of the month |
| 4. Month | 1 - 12 (or JAN - DEC) | * , - / | Month of the year |
| 5. Day of Week | 0 - 6 (SUN - SAT) | * , - / ? L # | Weekday identifier (0 = Sunday) |
Understanding Special Symbols
- • Asterisk (`*`): Wildcard representing every possible value in that field.
- • Slash (`/`): Step value increments. For instance, `*/15` in the minute field means “every 15 minutes”.
- • Comma (`,`): Value list separator. For example, `1,15,30` triggers on the 1st, 15th, and 30th minute.
- • Hyphen (`-`): Continuous range specifier. E.g., `1-5` in Day of Week triggers Monday through Friday.
Server Timezone Pitfalls
A frequent production mistake occurs when developers schedule backups at `0 2 * * *` expecting 2:00 AM local time, but the Docker container or cloud instance operates in UTC. Always synchronize scheduler timezones with system infrastructure.