The length of a Chinese sword can vary depending on the specific type of sword and its intended use. Chinese swords come in various styles, each with its own characteristic length. However, some general guidelines can be given:

1. Jian: The jian is a traditional Chinese double-edged straight sword. It typically has a blade length ranging from 28 to 31 inches (70 to 80 centimeters), although variations can occur.
2. Dao: The dao is a single-edged Chinese saber. The blade length of a dao can range from 20 to 30 inches (50 to 75 centimeters) or longer.
3. Piandao: The piandao is a broad-bladed Chinese saber. It has a wider blade compared to the dao, and its blade length can range from 24 to 36 inches (60 to 90 centimeters) or longer.
4. Wodao: The wodao, also known as the "martial saber," is a larger Chinese saber with a curved blade. Its blade length can vary from around 28 to 36 inches (70 to 90 centimeters) or longer.

These are general ranges for the blade lengths of common Chinese swords. It's important to note that the lengths can vary depending on the specific sword, regional variations, historical periods, and the preferences of swordsmiths or users.

In summary, the length of a Chinese sword can vary depending on the specific type and style. Jian blades are typically around 28 to 31 inches (70 to 80 centimeters), while dao blades can range from 20 to 30 inches (50 to 75 centimeters). The piandao and wodao can have longer blades, ranging from 24 to 36 inches (60 to 90 centimeters) or longer.