A cron expression is a string comprised of six or seven fields separated by white space. Fields can contain any of the allowed values, along with various combinations of the allowed special characters for that field. Cron expressions can be as simple as * * * * ? * or as complex as 0/5 14,18,3-39,52 * ? JAN,MAR,SEP MON-FRI 2002-2010.
Fields can contain any of the allowed values alone with various combinations of the allowed special characters for that field.
| Field Name | Allowed Value | Allowed Special Characters |
|---|---|---|
| Seconds | 0-59 | , - * / |
| Minutes | 0-59 | , - * / |
| Hours | 0-23 | , - * / |
| Day-of-Month | 1-31 | , - * ? / L W |
| Month | 1-12 or JAN-DEC | , - * / |
| Day-of-Week | 1-7 or SUN-SAT | , - * ? / L # |
| Year (Optional) | empty, 1970-2199 | , - * / |
| Character | Description |
|---|---|
| * | Asterisks indicate that the cron expression matches for all values of the field. For example, "*" in the minute field means every minute. |
| ? | Question marks are used to specify 'no specific value' and is allowed for the day-of-month and day-of-week fields. It is used instead of the asterisk (*) for leaving either day-of-month or day-of-week blank. |
| - | Hyphens are used to define ranges. For example, "10-12" in the hour field means the hours of 10, 11, and 12. |
| , | Commas are used to separate items of a list. For example, "MON,WED,FRI" in the day-of-week field means the days Monday, Wednesday, and Friday. |
| / | Forward slash are used to indicate increments. For example. "0/15" in the seconds field means the seconds 0, 15, 30, and 45. Additionally, "1/3" in the day-of-month field means every 3 days starting on the first day of the month. |
| L | Short-hand for "last" and is allowed for the day-of-month and day-of-week fields. The "L" character has a different meaning in each of the two fields. For example, "L" in the day-of-month field means the last day of the month. If used in the day-of-week field, it means 7 or SAT. However, if used in the day-of-week field after another value, it means the last xxx day of the month. For example, "6L" in the day-of-week field means the last Friday of the month. |
| W | Short-hand for "weekday" and is allowed for the day-of-month field. The "W" character is used to specify the weekday nearest the given day. For example, "15W" in the day-of-month field means the nearest weekday to the 15th of the month. Therefore, if the 15th is a Saturday, the job runs on Friday the 14th. The "L" and "W" characters can be combined in the day-of-month field. For example, "LW" means the last weekday of the month. |
| # | Hash marks specify constructs. For example, "6#3' in the day-of-week field means the third Friday of the month. |
| Expression | Description |
|---|---|
| 0 0 12 * * ? | Triggered to run at 12:00 p.m. (noon) every day |
| 0 15 10 ? * * | Triggered to run at 10:15 a.m. every day |
| 0 15 10 * * ? | Triggered to run at 10:15 a.m. every day |
| 0 15 10 * * ? * | Triggered to run at 10:15 a.m. every day |
| 0 15 10 * * ? 2005 | Triggered to run at 10:15 a.m. every day during the year 2005 |
| 0 * 14 * * ? | Triggered to run every minute starting at 2:00 p.m. and ending at 2:59 p.m., every day |
| 0 0/5 14 * * ? | Triggered to run every 5 minutes starting at 2:00 p.m. and ending at 2:55 p.m., every day |
| 0 0/5 14,18 * * ? | Triggered to run every 5 minutes starting at 2:00 p.m. and ending at 2:55 p.m., AND fire every 5 minutes starting at 6:00 p.m. and ending at 6:55 p.m., every day |
| 0 0-5 14 * * ? | Triggered to run every minute starting at 2:00 p.m. and ending at 2:05 p.m., every day |
| 0 10,44 14 ? 3 WED | Triggered to run at 2:10 p.m. and at 2:44 p.m. every Wednesday in the month of March |
| 0 15 10 ? * MON-FRI | Triggered to run at 10:15 a.m. every Monday, Tuesday, Wednesday, Thursday and Friday |
| 0 15 10 15 * ? | Triggered to run at 10:15 a.m. on the 15th day of every month |
| 0 15 10 L * ? | Triggered to run at 10:15 a.m. on the last day of every month |
| 0 15 10 L-2 * ? | Triggered to run at 10:15 a.m. on the 2nd-to-last last day of every month |
| 0 15 10 ? * 6L | Triggered to run at 10:15 a.m. on the last Friday of every month |
| 0 15 10 ? * 6L 2002-2005 | Triggered to run at 10:15 a.m. on every last Friday of every month during the years 2002, 2003, 2004 and 2005 |
| 0 15 10 ? * 6#3 | Triggered to run at 10:15 a.m. on the third Friday of every month |
| 0 0 12 1/5 * ? | Triggered to run at 12:00 p.m. (noon) every 5 days every month, starting on the first day of the month |
| 0 11 11 11 11 ? | Triggered to run every November 11 at 11:11 a.m. |