Picking the right sandpaper doesn't have to be complicated. Once you know what each grit is designed to do, it's a lot easier to choose the right one for the job. Starting with the right grit and working your way through the progression gives you a cleaner finish, uses less sandpaper, and saves time in the long run.
Take a look at our 3M sandpaper grit chart, from coarse to ultra-fine, to see what each grit range is best for. We'll also break down the differences between 3M Cubitron ceramic abrasives, aluminum oxide, and silicon carbide so you can choose the right abrasive for the material you're working with. Whether you're sanding wood, metal, auto body panels, or drywall, using the right sandpaper makes a noticeable difference.
Shop 3M Sandpaper Sheets & RollsWhat Do Grit Numbers Actually Mean?
The grit number on sandpaper tells you how coarse or fine the abrasive is. It's tied to the size of the abrasive particles bonded to the sheet. A low number like 40 or 60 means the particles are large and coarse. They remove material fast and leave a rough surface. A high number like 320 or 400 means the particles are much smaller. They cut slower and leave a smoother finish.
It's that simple. Lower number equals a rougher cut. Higher number equals a finer finish. The trick is knowing which range to use for which job, and in what order to work through the grits.
Most sandpaper sold in the U.S. uses the CAMI standard, set by the Coated Abrasive Manufacturers Institute. You'll also see P-grades on a lot of 3M products, which follow the European FEPA standard. In the coarse and medium ranges the two systems line up closely. They start to drift apart in the finer grits, where a P-grade and a CAMI grade with the same number are not identical. For most trade work, the categories below apply to both, but it's worth knowing why you'll see both a plain number and a "P" number on the shelf.
3M Sandpaper Grit Chart
Here's the full grit chart from coarse to ultra-fine. Use it as a quick reference for what each range is built to do.
| Grit Range | Category | What It Does |
|---|---|---|
| 40-60 | Extra Coarse / Coarse | Heavy material removal, rough shaping, stripping paint or varnish |
| 80-120 | Medium | Smoothing rough surfaces, removing mill marks and deep scratches |
| 150-220 | Fine | Final bare surface prep before stain or finish, light smoothing |
| 320-400 | Very Fine | Between-coat sanding, pre-primer, light metal finishing |
| 600-800 | Ultra Fine | Final sanding before paint, between paint coats |
| 1000-1500 | Micro Fine | Wet sanding after primer or clear coat, leveling |
| 2000-3000 | Polishing | Final polish prep, clear coat finishing and buffing |
3M Sandpaper Grit Chart by Application
Different trades use different grits, and most jobs mean working through several grit ranges in sequence. Here's how the grit chart maps across the four most common trade applications. Use this as a quick reference before you grab your next sheet.
Choosing the Right Grit for Woodworking
Wood is one of the more forgiving materials to sand, but it's also where a lot of guys go wrong. The most common mistake is starting too fine. If you're working rough lumber or a surface with planer marks, start at 80 grit. It'll knock down those high spots fast without taking forever.
From there, work your way up. After 80 grit, move to 120, then 150 or 180. If you're staining the wood, stop at 180 or 220. Going finer than that closes up the wood's pores and the stain won't absorb evenly. If you're painting, you can go a bit finer before priming.
Between coats of finish, 320 grit is your go-to. It knocks down dust nibs and brush marks without cutting through the finish coat. For most wood work, a good aluminum oxide sheet handles every stage. The 3M 216U Gold line is a solid aluminum oxide paper that runs the full grit range, so you can step through it from rough sanding all the way to between-coat work with one product family.
3M Sandpaper for Woodworking
| Application | Recommended Grit | 3M Product |
|---|---|---|
| Rough shaping, strip paint | P80 | 3M 216U Gold Abrasive Sheet, P80, 9 in x 11 in |
| Remove mill marks, initial smooth | P120 | 3M 216U Gold Abrasive Sheet, P120, 9 in x 11 in |
| Pre-stain / pre-finish sanding | P150 - P220 | 3M 216U Gold Abrasive Sheet, P180, 9 in x 11 in |
| Between finish coats | P400 | 3M 216U Gold Abrasive Sheet, P400, 9 in x 11 in |
See the full range of aluminum oxide sheets here: 3M Sandpaper Sheets & Rolls.
Choosing the Right Grit for Metal Work
Metal is less forgiving than wood. You need the right abrasive mineral, not just the right grit. For heavy work like removing rust, scale, or weld spatter, 40 to 60 grit with a ceramic or zirconia mineral cuts hard and holds up. Standard aluminum oxide paper works for lighter metal work, but it dulls faster on hard steel.
For general surface prep before welding or painting, 80 to 120-grit gets the surface ready without leaving too deep a scratch pattern. Before you prime bare metal, 180 to 220 grit gives you a clean surface with enough tooth for the primer to grip.
3M Cubitron II sandpaper is a strong choice for metal work. It uses precision-shaped ceramic grain, which means the abrasive is engineered into consistent triangular shapes instead of the randomly shaped grain on conventional paper. Those shaped grains slice through metal and fracture to keep sharp edges exposed, so the paper cuts faster, runs cooler, and lasts longer than standard abrasives. That matters on long grinding passes on heavy steel.
3M Sandpaper for Metal Work
| Application | Recommended Grit | 3M Product |
|---|---|---|
| Rust / scale removal, weld cleanup | 40+ | 3M 737U Cubitron II Hookit Sheet Roll, 40+ |
| General surface prep | 80+ - 120+ | 3M 737U Cubitron II Hookit Sheet Roll, 120+ |
| Pre-paint / pre-prime | P180 - P220 | 3M 216U Gold Abrasive Sheet, P220, 9 in x 11 in |
| Light finishing / deburring | 320+ | 3M 737U Cubitron II Hookit Sheet Roll, 320+ |
Browse the full Cubitron II lineup here: 3M Cubitron II Abrasives.
Choosing the Right Grit for Auto Body and Paint Prep
Auto body is where grit selection really matters. Each stage in the process has a specific grit range, and skipping steps leaves scratch marks that show up under the paint. Body technicians typically work through five to seven different grits on a single panel from start to finish.
Start at 40 to 80 grit to shape body filler. Move through 80 to 180 to knock it down and blend the edges. Before you spray primer, 220 to 320 grit prepares the surface. After primer, 400 to 600 grit scuffs before paint. After the base coat, 800 grit works between coats. After clear coat, 1500 grit or finer for wet sanding, then 2000 and above for polishing.
3M Wetordry sandpaper is the standard for wet sanding in auto body work. The silicon carbide mineral on those sheets cuts clean and doesn't load up when you're working through primer or clear coat. Silicon carbide is harder and sharper than aluminum oxide, which is exactly what you want for the fine, wet work at the end of a paint job.
A quick reminder on wet sanding: keep the surface and the paper wet the whole time. The water floats away the sanding residue so it doesn't clog the paper or put deep scratches back into the surface you just leveled. Wipe the panel down and check your work often under good light.
3M Sandpaper for Auto Body and Paint Prep
| Application | Recommended Grit | 3M Product |
|---|---|---|
| Scuff before primer / between coats | P400 | 3M 216U Gold Abrasive Sheet, P400, 9 in x 11 in |
| Final sand before paint | P600 | 3M 216U Gold Abrasive Sheet, P600, 9 in x 11 in |
| Wet sand after primer | 1000 - 1200 | 3M 401Q Wetordry Sheet, 1000 Grit, 9 in x 11 in |
| Level orange peel in clear | 1500 | 3M 401Q Wetordry Sheet, 1500 Grit, 9 in x 11 in |
| Wet sand clear coat | 2000 | 3M 401Q Wetordry Sheet, 2000 Grit, 9 in x 11 in |
| Pre-compound polish | 3000 | 3M 401Q Wetordry Sheet, 3000 Grit, 9 in x 11 in |
See all wet and dry sheets here: 3M Sandpaper Sheets & Rolls.
Choosing the Right Grit for Drywall
Drywall sanding is a different animal. You're not shaping a hard material, you're smoothing dried joint compound so it disappears under paint. The grits you use are narrower than the other trades, and going too coarse will chew up the paper facing on the drywall itself, which creates fuzz you'll have to deal with later.
For knocking down high spots and ridges in dried compound, 80 to 120 grit does the job. For the final pass that gets the joints flat and smooth, step up to 150 to 220 grit. You rarely need anything finer than 220 on drywall. Anything past that is wasted effort, since primer and paint will fill the fine scratch pattern that a 150 to 220 grit leaves behind.
One thing worth mentioning for drywall specifically: dust control. Drywall dust is fine and it gets everywhere. A lot of guys run mesh screen abrasives or dust-free sanding systems on drywall for that reason. The grit ranges stay the same, but the format helps keep the air and the job site cleaner.
3M Sandpaper for Drywall
| Application | Recommended Grit | 3M Product |
|---|---|---|
| Remove high spots, ridges in compound | P100 - P120 | 3M 216U Gold Abrasive Sheet, P100, 9 in x 11 in |
| Initial smoothing of joint compound | P120 | 3M 216U Gold Abrasive Sheet, P120, 9 in x 11 in |
| Final smoothing before primer | P150 - P220 | 3M 216U Gold Abrasive Sheet, P150, 9 in x 11 in |
Browse all abrasive sheets and rolls here: 3M Abrasive Sheets & Rolls.
Why You Work Through Grits in Order
No matter the trade, the same rule holds: don't skip too many grit steps at once. Each grit is designed to remove the scratch pattern left by the grit before it. If you jump from 80 grit straight to 220, the finer paper has to work a lot harder to erase those deep 80-grit scratches, and often it just doesn't fully get them out. You end up seeing them later under stain or paint.
The common approach is to roughly double the grit number as you step up, or move in reasonable jumps like 80 to 120 to 180 to 220. It feels slower, but it's faster overall because each step does its job and you're not fighting scratches at the end. Start as coarse as the job needs and no coarser, then climb.
The Bottom Line on Sandpaper Grit
Picking the right grit isn't complicated once you understand the chart. Low numbers cut fast and rough, high numbers finish smooth, and the job is a matter of starting in the right range and climbing through the grits in order. Match the mineral to the material too: aluminum oxide for general work, ceramic like Cubitron II for heavy metal, and silicon carbide Wetordry for fine wet sanding on paint.
Once you know the grit you need, you can find the full range of 3M sheets and rolls at Pro Work Supply here: 3M Sandpaper Sheets & Rolls.
Shop All 3M SandpaperFrequently Asked Questions
What grit sandpaper should I start with on rough wood?
For rough lumber or a surface with planer or mill marks, start at 80 grit. It removes the high spots fast without eating through too much material. From there, step up to 120, then 150 or 180. If you're staining, stop around 180 to 220 so the wood still takes stain evenly. Starting finer than 80 on rough stock just makes the job take longer.
What grit sandpaper do I use for metal before painting?
For bare metal before primer or paint, 180 to 220 grit is the sweet spot. It leaves the surface clean with enough tooth for the primer to grip, but not so deep a scratch that it telegraphs through the finish. If you're cleaning up rust, scale, or welds first, start much coarser at 40 to 80 grit with a ceramic paper like Cubitron II, then work up to the 180 to 220 range for the final prep.
What's the difference between CAMI grit and P-grit?
CAMI is the U.S. grading standard and P-grit is the European FEPA standard. In the coarse and medium ranges they're close enough that you can treat the numbers as roughly the same. They start to separate in the fine grits, so a P600 and a 600 CAMI are not identical. For most shop and job site work the difference doesn't change how you sequence your grits, but it's why you'll see both a plain number and a 'P' number on 3M sheets.
What is 3M Cubitron sandpaper and when should I use it?
Cubitron is 3M's precision-shaped ceramic abrasive. Instead of randomly shaped grain, the abrasive is engineered into consistent triangular shapes that slice through material and fracture to keep sharp edges exposed. The result is a faster cut, less heat, and longer life than conventional aluminum oxide. It shines on metal, especially heavy stock removal, weld cleanup, and hard steel where standard paper dulls quickly.
What grit is best for wet sanding auto body clear coat?
For wet sanding clear coat, most techs work in the 1500 to 3000 grit range depending on the stage. Use 1500 to level orange peel, 2000 for a finer wet sand, and 2500 to 3000 to prep for machine polishing and compounding. 3M Wetordry silicon carbide sheets are made for this. Keep the surface wet the whole time so the paper doesn't load up and put fresh scratches back in.
What grit sandpaper should I use on drywall?
For drywall, stick with 80 to 120 grit to knock down ridges and high spots in dried compound, then finish with 150 to 220 grit for a smooth surface before primer. You rarely need anything finer than 220. Going too coarse can tear the paper facing on the drywall and create fuzz, so don't reach for anything below 80 unless you're leveling a bad high spot.
Can I skip grits to save time?
You can skip one step, but skipping several usually costs you more time than it saves. Each grit is built to remove the scratches from the grit before it. Jump too far, say from 60 straight to 180, and the finer paper struggles to clear the deep scratches, so they show up later under finish. Move in reasonable steps, roughly doubling the number or climbing 80 to 120 to 180 to 220, and the whole job goes faster.