Zhuang characters, or Sawndip [θaːu˨˦ɗip], are logograms derived from Han characters and used by the Zhuang people of Guangxi, China to write the Zhuang languages. In Mandarin Chinese, these are called Gǔ Zhuàngzì (Chinese: 古壮字; literally "old Zhuang characters") or Fāngkuài Zhuàngzì (方块壮字; "square shaped Zhuang characters"). Sawndip (Sawndip: ) is a Zhuang word that means "immature character". The Zhuang word for Chinese characters used in the Chinese language is sawgun (Sawndip: 倱; lit. "original writing system") (saw meaning character or book, and gun meaning the Han Chinese ethnicity, cognate to 漢).

How long Sawndip have been used for is unclear. Several "vernacular characters" (Tǔsú zì 土俗字) from Guangxi are recorded in two Song dynasty books, Zhou Qufei's Lǐngwài dàidá (嶺外代) and Fan Chengda's Guìhǎi yúhéng zhì (桂海虞衡志). Some trace them back to the Tang dynasty, citing a stele from 689 entitled Zhì chéng bēi (智城碑), which, though written in Chinese, contains a number of non-standard characters. The fact that Zhuang readings of borrowed Chinese characters often match Early Middle Chinese also suggests an early date, but these could also be explained as later borrowings from conservative Pinghua varieties. In contrast, scholars studying the similar script used for the closely related Bouyei language in Guizhou associate the origin of that script with the introduction of Chinese officials in the early Qing dynasty.