The comparison between a katana and a ninjato in terms of which one is "better" depends on the specific criteria, combat style, and intended use. However, it's important to note that the term "ninjato" is not historically documented and is largely considered a modern invention or a product of fictional representation. Nonetheless, for the purpose of comparison, here are some considerations:

1. Design and Blade Shape: The katana is known for its curved, single-edged blade with a long grip, designed for versatility in cutting, slashing, and thrusting techniques. The blade shape of the katana is optimized for efficient cutting motions. The ninjato, as depicted in popular culture, is often portrayed as a straight-bladed sword with a shorter length, resembling a tanto or a wakizashi. However, it is important to recognize that the concept of the ninjato is not historically supported.
2. Combat Style and Tactics: The katana was the primary weapon of the samurai, designed for skilled one-on-one combat and versatility in different battle scenarios. It excelled in close-quarters engagements and was known for its cutting ability. The ninjato, as depicted in popular culture, is often associated with ninja characters and their stealthy and covert operations. Its specific combat style and tactics may vary depending on the portrayal, but it is often depicted as a weapon suited for quick, agile strikes and concealment.
3. Cultural Significance and Historical Context: The katana carries significant cultural and historical importance as the iconic sword of the samurai in feudal Japan. It represents honor, craftsmanship, and the warrior ethos of the samurai class. The ninjato, as mentioned earlier, is not based on historical evidence and is primarily a product of modern fiction and media portrayals.
4. Availability and Historical Accuracy: It is important to recognize that the depiction and availability of "ninjato" swords in real-world historical contexts are limited. The modern concept of the ninjato is largely influenced by fictional representations rather than historical records.

Ultimately, determining which sword is "better" depends on the specific criteria, intended use, combat style, and personal preferences. While the katana has a well-established historical background and recognized design, the concept of the ninjato is not rooted in historical accuracy. The preference for one sword over the other can also be influenced by personal taste, cultural significance, and individual combat style.