Cornerstone guide
Sandpaper grit chart, coarse to fine.
Every grit from 40 to 3000. Pick your climb.
Sandpaper runs from coarse to fine. The number on the back is the size of the abrasive particles glued to the backing. Lower number = bigger particles = more aggressive cut = rougher finish. Higher number = finer particles = smoother finish. That's the entire concept. The complication is that there are two numbering systems on the shelf, and above 220 they stop agreeing.
The coarse-to-fine ladder
Every project climbs from coarse to fine. Start low, work your way up. Skip a rung and you'll sand straight through the finish.
The chart, coarse to fine
| Grit | Class | Best use |
|---|---|---|
| 40 | Extra Coarse | Heavy stock removal, paint stripping, rough lumber. |
| 60 | Coarse | Aggressive shaping, rust removal, knocking down old finish. |
| 80 | Coarse | The first real pass on hardwood. Where most projects begin. |
| 100 | Medium | Smoothing rough wood. Last grit before primer in most paint prep. |
| 120 | Medium | The everyday workhorse grit. Most projects live here. |
| 150 | Medium-Fine | Pre-paint smoothness. Ready for primer. |
| 180 | Fine | Pre-stain hardwoods. Soft enough not to leave swirls. |
| 220 | Fine | Pre-finish. Between coats of stain or polyurethane. |
| 320 | Very Fine | Between top-coat layers. Glass-smooth feel. |
| 400 | Extra Fine | Wet sanding clear coat. Plastic finishing. |
| 600 | Super Fine | Lacquer between coats. Auto primer prep. |
| 800 | Ultra Fine | Auto color-coat sanding. Pre-polish on metal. |
| 1000 | Ultra Fine | Wet sanding paint. Pre-compound on metal. |
| 1500 | Micro Fine | Polishing prep. Removes orange-peel. |
| 2000 | Micro Fine | Pre-mirror polish. Auto clear-coat finishing. |
| 3000 | Mirror | Final polish prep. Right before compound. |
CAMI vs P-grade vs microns
Two standards share the shelf. CAMI (ANSI B74.12/B74.18) is the American system: a bare number on the back, the way most US hardware-store paper is marked. FEPA (ISO 6344) is the European one, printed with a P in front: P120, P400, P1500. Festool, Mirka and Norton 3X are P-graded; 3M Wetordry prints bare numbers.
Up to 220 the two agree closely enough not to matter. Above it they part ways, fast. A CAMI 400 sheet averages about 23 microns, which puts it beside a P800, not a P400. A CAMI 600 is about a P1200. Mix brands mid-climb and the stray scratch you can't sand out is usually this table's fault, not yours.
| Avg. particle | CAMI (US) | FEPA P (EU) |
|---|---|---|
| 764 µm | · | P24 |
| 708 µm | 24 | · |
| 642 µm | · | P30 |
| 632 µm | 30 | · |
| 538 µm | · | P36 |
| 530 µm | 36 | · |
| 425 µm | 40 | P40 |
| 348 µm | 50 | · |
| 336 µm | · | P50 |
| 269 µm | · | P60 |
| 265 µm | 60 | · |
| 201 µm | · | P80 |
| 190 µm | 80 | · |
| 162 µm | · | P100 |
| 140 µm | 100 | · |
| 125 µm | · | P120 |
| 115 µm | 120 | · |
| 100 µm | · | P150 |
| 92 µm | 150 | · |
| 82 µm | 180 | P180 |
| 68 µm | 220 | P220 |
| 58.5 µm | · | P240 |
| 53 µm | 240 | · |
| 52.2 µm | · | P280 |
| 46.2 µm | · | P320 |
| 40.5 µm | · | P360 |
| 36 µm | 320 | · |
| 35 µm | · | P400 |
| 30.2 µm | · | P500 |
| 28 µm | 360 | · |
| 25.8 µm | · | P600 |
| 23 µm | 400 | · |
| 21.8 µm | · | P800 |
| 20 µm | 500 | · |
| 18.3 µm | · | P1000 |
| 16 µm | 600 | · |
| 15.3 µm | · | P1200 |
| 12.6 µm | 800 | P1500 |
| 10.3 µm | 1000 | P2000 |
| 8.4 µm | · | P2500 |
Read it as one ladder sorted by particle size: anything on the same row or the next row is interchangeable in practice; shaded rows are where the two scales land on the same size. Sizes are average particle diameters from the published CAMI and FEPA tables (sources: Wikipedia, "Sandpaper" grit table (rev. 1127917881) ; Klingspor coated abrasives grit chart ). Those tables stop at P2500 and CAMI 1000. Above that, makers grade their own way: 3M's Trizact uses its own A-numbers, which don't line up with FEPA microns; 3M pairs A5 with P3000.
Holding one number and need the other? The grit converter takes a P-grade, a CAMI number, microns or a Trizact A-grade and gives you the rest, with a page for every P-grade from P40 to P5000.
Brand grit charts
Every line counts a little differently. These pages translate one brand at a time, grade by grade, and name the product at each step.
- 3M Wetordry → Silicon carbide on waterproof paper. The US numbering that quietly runs finer than the P-grade with the same digits.
- 3M Trizact → A-grades decoded by 3M’s own table, A5 = P3000, plus what P5000 is for.
- Scotch-Brite hand pads → Color is a grade, not a grit. 3M’s own names and minerals for maroon, gray, white and tan.
- Norton 3X → P-graded, heat-treated aluminum oxide, open coat. Every grade from P60 to P400 in microns.
- Festool Granat → Ceramic plus aluminum oxide, P-graded, anti-clog. With the Rotex vs ETS question answered.
- Mirka Abranet → Abrasive on a polyamide net, so the dust leaves through the whole disc. P-graded.
3M at every stage
- 40–80 grit: 40-grit sheets, aluminum oxide for aggressive stock removal
- 100–220 grit: Pro Grade Precision pack (80–320 assorted)
- 600–1500 grit: Wetordry assorted, silicon carbide for wet sanding between coats
- 1000–3000 grit: 2000-grit and 3000-grit Wetordry sheets for mirror finishes
The climb
Every project is a climb up the grit ladder. Skip a rung and you'll see the scratches from the last grit through everything that follows. The classic mistake is jumping from 80 to 220; it feels efficient until you stain the wood and the swirl marks show up like fingerprints.
A safe rule: never skip more than one grit step. 80 → 100 → 120 → 150 → 180 → 220 is the slow way. 80 → 120 → 180 → 220 is the working pro's way. 80 → 220 is the way you'll redo the project.
Coarse, medium, fine: what the words mean
- Extra Coarse (24–40): Floor refinishing. Stripping old finishes off rough lumber. Aggressive shaping.
- Coarse (60–80): The first real pass on most projects. Softwood smoothing. Old paint removal.
- Medium (100–150): The everyday workhorse range. Cabinet building. Pre-paint prep.
- Fine (180–220): Hardwoods before stain. Drywall. The "smooth to the touch" benchmark.
- Very Fine (320–400): Between coats of finish. Wet sanding paint primer.
- Extra/Super Fine (600–800): Auto color-coat work. Fine metal finishing.
- Ultra Fine (1000–1500): Wet sanding clear coat. Polishing prep.
- Micro/Mirror (2000–3000): The last sanding step before compound. Show-finish territory.
Wet vs. dry
Most sandpaper is dry-only. Wet/dry sandpaper (silicon carbide grain on a waterproof backing) lets you sand under a stream of water: keeps the surface cool, flushes the swirl, gives a glassy finish. Used for clear coat, lacquer, plastic restoration, and anything where heat is the enemy. Dry-only paper turns to mush if it gets wet.
Material: what's actually doing the cutting
- Aluminum oxide: The default. Cheap, durable, fine for wood and most metal. 80% of consumer sandpaper.
- Silicon carbide: Sharper, faster cut. Brittle. Used in wet/dry, glass, ceramic, plastic.
- Ceramic (Cubitron, Granat): Engineered grain that fractures into fresh sharp edges as it wears. Cuts faster, lasts longer, costs more. Pro choice for hardwoods and stock removal.
- Zirconia alumina: Tough and hot. The metal-shop standard for belts and flap discs.
- Garnet: Old-school natural mineral. Mild cut, fine finish. Niche; mostly for fine woodworking.
- Diamond: The only grain hard enough for stone, glass, and cured concrete.
Open coat vs. closed coat: why some paper clogs
Two sheets can wear the same grit number and behave nothing alike, and the reason is how much of the backing the grain actually covers. Closed coat packs the abrasive across roughly 90–100% of the surface: more cutting points per pass, a faster cut, a finer scratch. Open coat leaves deliberate gaps between the grains, covering closer to 50–70%, so there's somewhere for the debris to go instead of packing into the paper.
That gap is the whole difference on soft, gummy, resinous work. Paint, drywall mud, softwoods, pine sap, aluminum: anything that throws a lot of loose swarf will pack a closed-coat sheet solid in a few strokes, and a loaded sheet stops cutting and starts burnishing. Open coat keeps its appetite longer on that material. On hard, clean-cutting stock (hardwoods, steel, cured finish), the fine dust never threatens to clog, so closed coat's denser grain is the faster, finer choice. Match the coat to what the surface sheds, not just to the number.
The related trick is no-load (or stearated) paper: a soft, soap-like zinc-stearate dressing over the grain, usually a pale grey or white powder you can feel. It's a dry lubricant that keeps swarf from welding into the grit, which is why it shines between coats of finish and on painted surfaces that gum up ordinary paper. One honest caveat: the stearate can leave a faint residue that some waterborne finishes fish-eye over, so wipe the surface down before a water-based topcoat, or reach for wet sanding instead, where a flood of water does the anti-clogging work and rinses clean.
The rest of the site is built around this chart. Tap any grit number in the chart to see the SKUs we recommend at that level.
Guides by project type
- What grit sandpaper for woodworking?: The full 80–220 sequence, by task and wood type.
- What grit sandpaper for auto body?: Where the chart runs all the way to 3000, primer, color, and clear coat.
- How to wet sand: The technique that unlocks the high end of the chart without clogging.
Questions about the grit chart
What does a sandpaper grit chart from coarse to fine actually show?
A grit chart maps the full spectrum from coarse (low numbers, aggressive cut) to fine (high numbers, smooth finish). The chart above shows every common grit from 40 to 3000. Each step represents a finer particle size. Most projects move up the ladder: start coarse to remove stock or old finish, work through medium grits to smooth, and finish fine to prepare for stain or clear coat.
Can I skip grits when climbing coarse to fine?
No. Skip a rung and you'll sand through the scratches from the last grit. The rule: never jump more than one grit step. 80 → 120 → 180 → 220 is the pro path. 80 → 220 is the way you'll redo the project.
Where does the coarse-to-fine range start and end?
Coarse runs 24–80 grit (stock removal, stripping, aggressive shaping). Medium is 100–150 (smoothing, prep). Fine starts at 180 and runs to 3000 (finishing, wet sanding, mirror polish). Most DIY and woodworking projects live in the 80–220 range. Auto body and clear-coat work pushes into the 600–3000 fine territory.
3M coverage from coarse to fine
3M spans the full coarse-to-fine range with products at almost every step. Their Pro Grade assorted packs and individual sheets cover 40-grit aggressive work through 220-grit finishing, hitting the coarse and medium ranges that most projects live in. Their aluminum oxide formulations work well for wood, paint prep, and general stock removal.
The high end belongs to 3M's Wetordry silicon carbide line. Wet sanding at 1000 grit through 3000-grit mirror finishes is where 3M's reputation earns its premium price. Silicon carbide grain, a waterproof backing, and precision coating keep the surface cool and the finish glassy through the wet-sanding process. 3M also manufactures products across multiple form factors: sanding sponges, random orbital discs, and specialty rolls for contours and panel work.
Shopping by form factor helps narrow the choices. Browse our sheet selection for flat surfaces, discs for random orbital sanders, or belts for benchtop belt sanders. At each grit level, 3M is represented alongside other top performers.