Timezone Converter
Compare world times instantly. Convert between Seoul, New York, London, Tokyo and more β with live clock and DST detection.
Where Time Zone Math Goes Wrong
The reference system
Time zones are offsets from UTC, and each region's rules live in the IANA time zone database (IDs like `Asia/Seoul`, `America/New_York`). Whether scheduling or programming, working from these IDs β not memorized offsets β is what stays correct.
The three classic mistakes
1. Daylight saving time: the US and Europe shift by an hour in summer, and on different dates. A memorized 'SeoulβNY = 14 hours' breaks to 13 in summer. (Korea has no DST.) 2. Date boundaries: crossing zones can change the day β your 'Monday 9am' may be their Sunday night. Always confirm the date along with the time. 3. Fractional zones: India (UTC+5:30) and Nepal (UTC+5:45) exist; not every zone is a whole hour.
Scheduling tip: state the reference zone explicitly β '3pm KST (06:00 UTC)' β every time. It prevents nearly all cross-team meeting accidents.
Frequently Asked Questions
Related Tools
Sources & References
Content last reviewed: 2026-08-22