Cron Expression Parser

At every 15 minutes past hours 9 through 17, on days Monday through Friday

Every field is unambiguous, and the next runs above are in the timezone of this browser. That matters because a crontab follows the clock of the machine that holds it, including its daylight-saving changes. A job set for 01:30 runs twice on one night a year and not at all on another, which is why anything sensitive to exactly-once execution is better scheduled in UTC or given a lock.