Cixi, formerly romanized as Tzeki, is a county-level city under the jurisdiction of the sub-provincial city of Ningbo, in northeastern Zhejiang province, China. As of the 2020 census, its population was 1,829,488. Its urban agglomeration built-up (or metro) area, largely contiguous with Cixi plus the county-level city of Yuyao, had 3,083,520 inhabitants.

Cixi was part of the state of Yue in the Spring and Autumn period (770–476 B.C.). The county was set up in the Qin dynasty. At first it was called "Gouzhang" and has been using the name of "Cixi" since the Kaiyuan reign of the Tang dynasty (738 A.D.).^{[citation needed]}

Cixi City is located on the south of the economic circle of Yangtze River Delta, and is 60 km (37 mi) from Ningbo in the east, 148 km (92 mi) from Shanghai in the north and 138 km (86 mi) from Hangzhou in the west.

Cixi is located in the Zhejiang Province of eastern China and has a subtropical monsoon climate with an average temperature of 17 °C (63 °F).

Highway connections are provided to all major cities, typical travel times are 1.5 hours or less by car, including access to the four major airports, Ningbo Lishe International Airport, Hangzhou Xiaoshan International Airport, Shanghai Hongqiao Airport, and Shanghai Pudong International Airport. Shanghai and Ningbo are also the closest sea ports.

The Hangzhou Bay New District is located in the city.

Cixi is accelerating the construction of a mid-scale modern city, covering a total land area of 1,361 km² (525 sq mi) with a population of 1.83 million as of the 2020 census^{[citation needed]}, including 1.04 million registered permanent residents and one million temporary residents. Fifteen towns and five subdistricts are under the jurisdiction of Cixi City and there are 325 administrative villages including committees and communities.^{[citation needed]}

The city houses many Yue Kiln Sites, which are widely regarded^{[by whom?]} as one of the origin of Chinese porcelain.