The thickness of a Jian sword blade can vary depending on the specific design, historical period, and individual preferences. However, as a general guideline, the thickness of a Jian blade typically ranges from 4 to 8 millimeters (0.16 to 0.31 inches).

The Jian is a traditional Chinese straight sword with a double-edged blade. Its design focuses on balance, precision, and agility. The thickness of the blade is an important factor in determining its overall weight, flexibility, and cutting performance.

A Jian blade is usually thicker near the base (hilt) and gradually tapers towards the tip (point). This distribution of thickness helps optimize the blade's strength and balance. Thinner blades near the tip allow for quick and precise thrusts, while thicker sections near the hilt provide structural stability and durability.

It's worth noting that historical variations and individual preferences can lead to variations in blade thickness. The thickness of a Jian sword blade can also be influenced by factors such as the intended use, regional styles, and the skill and preferences of the swordsmith.

If you are specifically interested in a particular Jian sword or its dimensions, it is advisable to consult reputable sources or experts who specialize in Chinese swords or historical weaponry for more precise information.