Kanehira (古備前包平) has been celebrated since antiquity as one of the " Sanpei" (備前三平) — the Three of — alongside Takahira and Sukehira of the province. Active from the late period through the early period, Kanehira is consistently ranked among the smiths as "one of those with particularly outstanding skill." His renown is further elevated by the existence of the supreme named blade Ō-Kanehira, a National Treasure transmitted in the Ikeda family and "counted among the foremost celebrated blades under heaven." The has observed that signatures bearing the name Kanehira vary considerably — some are small and cut with a fine chisel, others are boldly rendered with thick strokes, and rare long inscriptions exist — leading to the scholarly position that "in there were multiple smiths using the name Kanehira," though whether these differences "reflect chronological differences within the smith's career" or the hands of distinct individuals remains, as the examiners note, "a problem for future research."
Kanehira's works characteristically present a slender, graceful with high , pronounced , and — features that "clearly display the characteristic features of its time." The forging consistently shows mixed with , frequently tending toward (standing grain), with well-adhering and . appears in various manifestations — , , and faint — and the steel is described as "bright and clear." The is founded on , variously mixed with , , and , accompanied by vigorous and . adheres thickly throughout, with abundant including , , , , and uchi-noke. The is "bright and clear," and the is typically with turnback, often exhibiting . Where appears at the , it is noted as "a feature sometimes encountered in works." Taken together, these qualities produce what the repeatedly describes as an "archaic fragrance characteristic of " — a quietness and depth of tone explicitly distinguished from the "flamboyant brilliance" of the Ō-Kanehira itself.
Across the designation records, the consistently praises Kanehira's works as achieving "an especially outstanding level of workmanship" and a "richly detailed" interpretation that "strongly manifests the style of ." The preservation of both and is described as (健全) — sound and well-preserved — with remarkable frequency, and blades are further commended for retaining excellent (肉置き). The surviving corpus encompasses , , and shortened , several preserving tangs with original signatures — a condition the examiners deem particularly "desirable." Works have been transmitted through distinguished collections including the Satake family of Akita, the family of Obi in , the Tatebayashi Akimoto family, the Kyōgoku family, and the Tokugawa shogunal house, and a number of blades are documented in the Kōzan . Whether understood as a single master or a small lineage of smiths sharing the name, the scholarly consensus positions Kanehira as a foundational figure whose works "fully display the particular virtues" of the school.