Shakkan-hō Pro Converter

Convert Japanese shakkan-hō to metric and imperial units instantly—area, volume, and weight. A professional tool for builders, stonemasons, and farmers.

Shakkan-hō Pro — Professional unit conversion & aggregation app

Overview Shakkan-hō Pro instantly converts between Japan's traditional shakkan-hō units and modern metric or imperial systems. Ideal for stoneworkers, builders, surveyors, farmers, real estate professionals and traders who need accurate, work-ready conversions and totals.

Who it's for • Stone industry — calculate sai (才) ⇄ cubic meters, cubic shaku volumes, and manage tombstone and stone block dimensions; sum multiple stone sizes for estimates. • Construction & architecture — convert ken, shaku, sun for drawings and precise measurements; convert tsubo ⇄ square meters for area planning. • Real estate — compute land area in tsubo, tan, se, chobu and present clear metric equivalents for listings and valuations. • Agriculture & forestry — manage fields in tan/are/chobu for yield estimates and subsidy paperwork. • Trade & export — convert pounds, yards, barrels, gallons between US/UK systems and metric. • Jewelry & precious metals — monme ⇄ grams, carat conversions and metal weight calculations.

Key features

Comprehensive unit coverage Length: ri, cho, jō, ken, shaku, sun, bu, rin, mō ⇄ km, m, cm, mm ⇄ mile, yd, ft, in Area: chōbu, tan, se, tsubo, gō ⇄ km², ha, a, m² ⇄ acre, yd², ft² Weight: kan, kin, monme, fun, rin ⇄ ton, kg, g ⇄ lb, oz, grain (carat supported) Volume: koku, to, shō, gō, sai, cubic-shaku ⇄ m³, L, mL ⇄ bbl, gal, qt, pt

Aggregate calculator • Auto-sum multiple conversion results (e.g., combine several stone blocks’ sai) • Keep historical calculations for quick reference • Calculate required order quantities for materials

Dimension-based volume calculations • Enter length × width × height in shakkan-hō to get m³ and sai • Ideal for stone, timber and material volume estimates

Professional accuracy • Up to 6 decimal places for high-precision needs • Scientific notation for very large/small values • Reliable for professional use

Usability • One-tap copy of results • Three adjustable font sizes • Dark mode • Supports 10 languages (Japanese, English, Simplified/Traditional Chinese, Korean, Spanish, German, Italian, French, Arabic)

Other benefits • Fully offline — no internet required • Lightweight and responsive UI • Clear conversion tables for quick checks • Secure local data storage only (no cloud sync by default)

Recommended users Architects, carpenters, stonemasons, real estate agents, farmers, exporters, gemologists, antiques appraisers, traditional craftsmen, land surveyors, construction consultants.

Shakkan-hō Pro brings Japan’s traditional measurement systems into modern workflows — precise, fast, and tailored for professionals.