China Standard Time

The time in China follows a single standard time offset of UTC+08:00, which is eight hours ahead of Greenwich Mean Time, despite China spanning five geographical time zones. The official national standard time is called Beijing Time (Chinese: 北京时间) domestically and China Standard Time (CST) internationally. The special administrative regions (SARs) maintain their own time authorities, with standards called Hong Kong Time (Chinese: 香港時間) and Macau Standard Time (Chinese: 澳門標準時間). There is no difference between Beijing time and the times in the SARs. In addition, double time standard is used in Xinjiang, with the alternative time standard being two hours slower than the Beijing Time (UTC+06:00), which is called Ürümqi Time (Chinese: 乌鲁木齐时间) or "Xinjiang Time" (Chinese: 新疆时间).

There was no nationwide time standard in China until the early 20th century. In imperial China, astrological predictions were conducted according to the time standard based on the locations of then capitals of the imperial dynasties. A summer time was observed in 1919 in Tianjin and Shanghai, and from 1935 to 1962 in parts of China.

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