How does a tachi differ from a katana in terms of length and curvature?
Updated Mar 2026
The tachi predates the katana by several centuries and differs in meaningful ways beyond simple blade length. A tachi typically measures over 70 cm along the cutting edge and features a more pronounced curvature (sori) distributed closer to the middle of the blade, compared to the katana's curvature concentrated toward the tang. Historically, the tachi was worn edge-downward suspended from a belt, while the katana was thrust through the obi edge-upward. For collectors, this distinction affects how the piece is properly displayed - a tachi is conventionally mounted with the edge facing downward on a wall rack, preserving its historical orientation.