AWS Lambda supports standard rate and cron expressions for frequencies of up to once per minute. EventBridge (CloudWatch Events) rate expressions have the following format.
rate(Value Unit)
Where Value is a positive integer and Unit can be minute(s), hour(s), or day(s). For a singular value the unit must be singular (for example, rate(1 day)), otherwise plural (for example, rate(5 days)).
Rate expression examples
| Frequency | Expression |
|---|---|
| Every 5 minutes | rate(5 minutes) |
| Every hour | rate(1 hour) |
| Every seven days | rate(7 days) |
Cron expressions have the following format.
cron(Minutes Hours Day-of-month Month Day-of-week Year)
Cron expression examples
| Frequency | Expression |
|---|---|
| 10:15 AM (UTC) every day | cron(15 10 * * ? *) |
| 6:00 PM Monday through Friday | cron(0 18 ? * MON-FRI *) |
| 8:00 AM on the first day of the month | cron(0 8 1 * ? *) |
| Every 10 min on weekdays | cron(0/10 * ? * MON-FRI *) |
| Every 5 minutes between 8:00 AM and 5:55 PM weekdays | cron(0/5 8-17 ? * MON-FRI *) |
| 9:00 AM on the first Monday of each month | cron(0 9 ? * 2#1 *) |
Note the following:
- If you are using the Lambda console, do not include the
cronprefix in your expression. - One of the day-of-month or day-of-week values must be a question mark (
?).
For more information, see Schedule expressions for rules in the EventBridge User Guide.