Using daylight-saving time rules

Most countries observing daylight-saving time have fixed daylight-saving time rules. Daylight-saving time in the United States starts for instance at 2:00 AM standard time on the second Sunday in March and ends at 2:00 AM daylight time on the first Sunday in November every year. Similarly, daylight-saving time in Central Europe always starts at 2:00 AM standard time on the last Sunday in March and ends at 3:00 AM daylight time on the last Sunday in October.

With daylight-saving time rules World Clock Deluxe lets you quickly specify daylight-saving time information.

To display daylight-saving time rules while you are defining a new city or editing an existing city, click the DST Rules button. To apply a daylight-saving time rule to the city you are adding or editing, select its country or region (e.g. Central Europe) in the DST Rules panel and click the Apply Rule button.

If your city's country or region does not appear in the DST Rules panel, then it either does not observe daylight-saving time or has no fixed daylight-saving time rule.

World Clock Deluxe lets you add, edit, duplicate and delete daylight-saving time rules.

To add a new rule, click the New Rule icon in the DST Rules panel toolbar. To edit or duplicate an existing rule, select it in the list and click the Edit or Duplicate icon in the toolbar. To delete one or more rules, select them and click the Delete icon in the toolbar or press the Delete key.