P150 sandpaper
100 µm grain
P150 (FEPA) · about 150 grit (CAMI) · 0.100 mm average particle
What P150 is for
Between the shaping grits and the finishing ones. Also the usual grit for smoothing filler.
The two scales
| FEPA (European) | P150 |
| CAMI (American) | about 150 |
| Average grain | 100 µm |
| Scales agree here? | Yes, near enough to substitute |
Nearby grits
| FEPA | CAMI | Grain | Typically |
|---|---|---|---|
| P80 | 80 | 201 µm | The usual first grit on bare timber |
| P100 | 100 | 162 µm | General sanding on softwood, and the point at which the surface starts to look intentional rather than attacked |
| P120 | 120 | 125 µm | The workhorse grit for wood before finishing |
| P150 | 150 | 100 µm | Between the shaping grits and the finishing ones |
| P180 | 180 | 82 µm | The last grit where P and CAMI still mean nearly the same thing |
| P220 | 220 | 68 µm | The last grit most woodwork needs before paint or stain, and the point where the two scales still agree closely enough to substitute one for the other without noticing |
| P240 | 220 | 58.5 µm | The first grit of the finishing range rather than the preparation range, and the first where the two scales visibly part company: P240 falls between CAMI 220 and 240 and matches neither |
| P280 | 240 | 52.2 µm | Fine finishing on hardwood, and between coats of varnish |
Frequently asked questions
Is P150 the same as 150 grit?
Close enough to treat as the same. Below about P180 the European and American scales agree; the divergence starts above it.
What grain size is P150?
An average grain of 100 µm — 0.100 mm. That figure is what the P number is defined by, which is why it is the reliable way to compare across scales.
What is P150 used for?
Between the shaping grits and the finishing ones. Also the usual grit for smoothing filler.
What comes before and after P150?
Coming up from coarse, P120 (125 µm) and then this; the next step finer is P180 at 82 µm. Skipping more than one step leaves scratches the finer paper cannot remove — the usual cause of a surface that looks fine dry and terrible once finish goes on.