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Grit Size Converter

Convert between different grit size standards: FEPA, ANSI, JIS, and micron measurements.

About Grit Sizes

Different standards use different numbering systems for abrasive grit sizes. This converter helps you find approximate equivalents across standards.

  • FEPA (P-Grade): ISO 6344 standard for coated abrasives. Micron values represent median particle size (d50).
  • ANSI/CAMI: US standard. Macrogrits (≤220) share the same designation numbers as FEPA P, though actual particle sizes differ slightly between standards. Above 220, ANSI uses a different numbering scale.
  • JIS: Japanese Industrial Standard R6001. Macrogrits use the same sieve-based numbering as FEPA/ANSI. Microgrits (above #220) diverge significantly in numbering.
  • Micron (μm): Particle size in micrometers per the FEPA P-grade specification.

Note: Cross-standard equivalents above P220 are approximate and matched by closest particle size, not by grit number. These standards define particle size differently (sieve analysis vs. sedimentation vs. laser diffraction), so exact equivalence is not possible. Always verify critical specifications with your abrasive supplier.

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