In traditional Japanese swordsmithing, it is a common misconception that katana blades are folded hundreds or thousands of times during the forging process. However, this notion is not entirely accurate.

Historically, the folding process involved in the creation of a katana blade was used to refine the steel and remove impurities, ensuring a strong and consistent blade. Swordsmiths would fold the steel multiple times, typically around 8 to 16 times, depending on the specific technique and desired outcome.

During each folding iteration, the swordsmith would heat the steel, hammer it, and then fold it over itself. This process helped distribute carbon and other elements evenly throughout the blade, creating a homogeneous structure and eliminating impurities.

While the exact number of folds can vary between swordsmiths and individual blades, the commonly cited range is around 8 to 16 folds. The folding process was an important step in the forging of a katana, contributing to its strength, flexibility, and overall quality.

It's worth noting that the number of folds alone does not determine the quality of a katana. The skill of the swordsmith, the choice of materials, and the overall craftsmanship are equally significant factors in creating a high-quality blade.

In modern times, not all katana blades are folded, as the traditional folding process can be time-consuming and require extensive skill. However, many contemporary swordsmiths who aim to create authentic reproductions or maintain traditional techniques may still incorporate folding as part of their sword-making process.

In summary, while there is no set number of times a katana blade is folded, it is generally folded around 8 to 16 times during the forging process to refine the steel and create a high-quality blade. The folding process is an important aspect of traditional Japanese swordsmithing, contributing to the strength and overall quality of the katana.