DST Boundary
Find times that vanish or repeat
Utilities
Result
Enter a local date, time, and time zone.
How to use
Enter local time
Enter the wall-clock date and time used by a schedule or job.
Choose a time zone
Use an IANA name such as America/New_York.
Inspect candidates
Change a zero-candidate time or explicitly choose an offset for two candidates.
Scope of the result
Results depend on the Intl time-zone data built into this browser. For critical schedules, verify against the actual runtime because laws and data versions can differ.
Frequently asked questions
- What is an ambiguous local time?
- During fall back, one wall-clock time occurs twice and maps to two UTC instants.
- What is a nonexistent local time?
- During spring forward, the clock skips a range that maps to no UTC instant.
- Can I enter a UTC offset instead?
- No. An IANA zone is needed to apply the region's transition rules.