Grit Table / standards / JIS R6001
Standard
Japanese national standard for abrasive grit sizes
JIS R6001 defines what each grit number means as a particle size. For the fine grades it specifies a distribution by sedimentation, not a single number: a coarse tail (d3), a median (d50), and a fine tail (d94). It is Japan's counterpart to FEPA and ANSI. Japanese waterstone numbers borrow from it, but makers are not bound to it (see the per-brand pages). The standard stops at #8000.
Standard distribution: d3 103 / d94 40.
Standard distribution: d3 97 / d94 33.
Standard distribution: d3 74 / d94 27.
Standard distribution: d3 66 / d94 23.
Standard distribution: d3 58 / d94 20.
Standard distribution: d3 50 / d94 16.
Standard distribution: d3 43 / d94 13.
Standard distribution: d3 37 / d94 11.
Standard distribution: d3 31 / d94 9.
Standard distribution: d3 27 / d94 7.
Standard distribution: d3 23 / d94 5.5.
Standard distribution: d3 20 / d94 4.5.
Standard distribution: d3 17 / d94 4.
Standard distribution: d3 11 / d94 2.
Standard distribution: d3 8 / d94 1.3.
Standard distribution: d3 5 / d94 0.8.
Standard distribution: d3 3.5 / fine tail not defined.