Which zone this page means. CET is winter time; CEST (UTC+2) applies from the last Sunday in March to the last Sunday in October. Europe changes on different dates from the United States, so the gap to US zones shifts for a few weeks each spring and autumn. South Korea does not observe daylight saving, so KST applies all year. It shares an offset with Japan.
CET is behind KST by 7 hours today
On 19 August 2026, Central European Time is on CEST at UTC+02:00 and Korea Standard Time is on KST at UTC+09:00. The gap between them is 7 hours, with KST ahead. So 9:00 am in CET is 4:00 pm in KST, and 5:00 pm in CET is 12:00 am in KST. Going the other way, see KST to CET.
The gap is not constant, and that is the part that catches people out
Central European Time is currently observing daylight saving and changes next on 25 October 2026, when clocks go back an hour. Korea Standard Time does not observe daylight saving at all, so the whole of the seasonal change comes from the CET side: the gap moves by an hour twice a year even though nothing changes in Korea Standard Time.
When you can actually both be at work
Taking a working day as 9:00 am to 5:00 pm local at each end, there is 1 overlapping hour in a normal day. In CET that window runs from 9:00 am to 10:00 am, which is 4:00 pm to 5:00 pm in KST. Anything outside it needs one side to start early or finish late.
Zone rules are set by legislation and change, sometimes at short notice. This page is built against tzdata 2026a, last reviewed 2026-08-18. Quarterly. Zone rules change by legislation, sometimes at short notice. Version and review date are shown on every zone page. The converter above reads your browser's own copy of the zone database, so if a rule has changed since this page was built the live answer follows the new rule.
Every convention used above — whether the start date counts, how month ends are clamped, which holidays close an office — is written out on the methodology page, including the daylight-saving rules behind the 7-hour gap above.