Cron schedules look simple until the scheduler timezone is different from the timezone in your head.
Traditional cron usually runs in the timezone configured on the server or cron daemon. If the server is set to UTC, then 0 9 * * * runs at 09:00 UTC, not necessarily 09:00 in your local timezone.
AWS EventBridge cron expressions are evaluated in UTC. EventBridge Scheduler can support timezone settings, but classic scheduled rules and many examples assume UTC. Cron Explainer labels AWS next-run previews accordingly.
Daylight saving time can make local schedules skip or repeat apparent clock times. UTC schedules avoid that ambiguity, while local-time schedules should be checked around DST transitions.
The main tool lets you choose a timezone for standard cron previews. For AWS cron expressions, the preview uses AWS-style UTC evaluation so the output lines up with how EventBridge interprets the expression.
