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Grit to Micron Chart
Sandpaper grit ↔ average particle size in microns, from stock removal to mirror polish.
Grit → Micron Reference
| Grit (FEPA P) | Avg particle (µm) | Surface feel |
|---|---|---|
| P60 | 269 | Heavy stock removal |
| P120 | 125 | Shaping |
| P180 | 82 | Blending |
| P240 | 58.5 | Fine sanding |
| P400 | 35 | Pre-polish |
| P800 | 21.8 | Wet sanding |
| P1500 | 12.6 | Fine finish |
| P2500 | 8.4 | Polishing prep |
| 1 µm paste | 1 | Mirror polish |
Rule of Thumb
Each full grit step removes roughly half the scratch depth. Jump no more than one grit class per pass or you leave deep scratches that the next grit cannot erase.
FAQ
Is FEPA P grit the same as CAMI?
No — P240 (FEPA) averages 58.5 µm while 240 (CAMI) is about 53.5 µm. They are close but not identical; always note the standard when quoting grit.
What grit for sharpening?
Coarse repair 120–320, edge refinement 800–2000, honing/polishing 4000–8000 (or strop with 1 µm compound).