A grit number measures one thing: the size of the abrasive particles doing the cutting. A 320-grit stone has roughly 46-micron particles that rip steel away quickly. An 8000-grit stone has particles a few microns across that mostly polish. Every practical decision in sharpening follows from that single fact plus one more: where you stop.
For most everyday carry folders, three stages cover everything. Something in the 320-400 range rebuilds a bevel, a 600-1,000 stone refines it, and a 2,000-3,000 finish is optional polish. Past 3,000 you are tuning feel, not function.
What a Grit Number Actually Measures
Grit is a particle-size rating, not a sharpness rating. The abrasive grains in a stone or sheet are graded by size, and the number on the label is a classification bucket, not an exact micron figure. The table below uses the coated-abrasive (CAMI/ANSI) scale, because that is where the published micron conversions are most consistent. Treat every figure as approximate.
| Grit | Approx. particle size | What it does to an edge | Typical job |
|---|---|---|---|
| 120 | ~125 micron | Reshapes geometry fast | Reprofiling a damaged or badly obtuse bevel |
| 220 | ~68 micron | Fast stock removal | Setting a new angle, fixing a chipped tip |
| 320 | ~46 micron | Removes 220 scratches | First stone for a dull but undamaged knife |
| 400 | ~35 micron | Refines the bevel | Medium stage on soft stainless |
| 600 | ~26 micron | Starts forming a clean apex | Bridge grit on most progressions |
| 800 | ~22 micron | Semi-refined edge | Good stopping point for working knives |
| 1,000 | ~18 micron | Apex is consistent and burr is small | Standard finish for budget stainless |
| 1,500 | ~13 micron | Light refinement | Finish for mid-carbide steels |
| 2,000 | ~10 micron | Noticeably polished | Slicing edge on harder steels |
| 3,000 | ~6.5 micron | Near-mirror bevel | Practical ceiling for most EDC use |
| 6,000+ | ~4 micron and finer | Polished, low-tooth edge | Push-cutting, woodworking, straight razors |
The jump that matters most is 320 to 600. That is where a ragged, burr-heavy apex becomes a stable one. Skipping it and going straight from a coarse stone to a 3,000-grit finisher is the single most common reason a knife feels sharp off the stone and dull a day later: the fine stone polishes the tops of the coarse scratches instead of removing them, leaving a weak, saw-toothed apex underneath.
The Standards Problem: 1000 Grit Is Not 1000 Grit
Three rating systems are in circulation and they do not agree: CAMI/ANSI used on most US-coated abrasives, FEPA (marked with a P, common on European papers), and JIS used on Japanese water stones. A JIS 1000 water stone is considerably finer than a CAMI 1000 sheet, and a FEPA P1000 sits somewhere between them.
Practically: never plan a progression across brands by grit number alone. Plan it by scratch pattern. If you move from stone A to stone B and the scratch marks from A are not gone after a reasonable amount of work, B is not doing its job regardless of what the labels say. The Wikipedia entry on coated abrasives{: target="_blank" rel="noopener noreferrer nofollow"} lists the CAMI and FEPA grading tables side by side, and the sharpening stone overview{: target="_blank" rel="noopener noreferrer nofollow"} covers how water-stone grading differs.
Diamond plates add a third wrinkle: they are usually sold by mesh, which counts wires per inch rather than particles, so a 600-mesh diamond plate cuts more like a 400-600 grit stone but leaves a different scratch shape.
The Three-Stage Ladder That Covers Most Edges
Instead of memorizing grits, build a ladder with one job per stage.
- Reset stage. The coarsest grit that will actually move the steel in a reasonable time. For a dull edge with intact geometry, 320-400. For a chipped or reprofiled edge, 220. Do not spend twenty minutes on a 1,000 stone trying to do a 320 job.
- Apex stage. 600-1,000. This is where you raise a burr along the full edge, then remove it. Most knives should be usable after this stage.
- Finish stage. 1,500-3,000, only if the knife will be used for push cutting or you want a cleaner bevel. On a working knife this stage is optional.
Two rules keep the ladder honest. First, each stage must fully erase the previous stage's scratches; if you can still see them under a light, you have not finished the stage. Second, never let the burr grow across stages. A burr formed at 320 and carried into a 3,000 stone will fold back and forth until the apex fatigues.
For a step-by-step method tied to specific steels, the steel-by-steel sharpening walkthrough covers cadence and stone choice; how to use a whetstone covers the physical technique.
Grit Progressions by Steel Class
The steel determines how much polishing it can actually hold. Low-alloy stainless with fine carbides will take a high polish and keep it. High-carbide steels resist abrasion, so they cut slowly on fine stones and their carbides can be pulled from a too-polished apex.
| Steel class | Catalog examples | Start | Apex | Finish | Why |
|---|---|---|---|---|---|
| Low-alloy stainless | AR-RPM9, 9Cr18MoV, AEB-L | 320 | 800-1,000 | 1,500 (optional) | Fine carbides polish evenly; toothy edges last well |
| Fine-grain stainless | 14C28N, Nitro-V | 320-400 | 800-1,000 | 2,000 | Responds quickly, holds a refined edge |
| Medium carbide | D2, 154CM, S35VN | 400 | 1,000 | 2,000-3,000 | Needs more work per grit step; skip nothing |
| High carbide | M390, Elmax, S90V | 600 | 1,000 | 2,000-3,000 max | Slow on fine stones; polishing past 3,000 adds effort, not durability |
High-carbide steels are the ones where cheap coarse stones cost you real time. If a 1,000-grit stone skates rather than bites on M390, the problem is the abrasive, not your technique: diamond or CBN cuts these steels consistently where aluminum oxide struggles. Knife Steel Nerds has a useful discussion of how grinding and abrasive choice affect the resulting edge in this article on grinder sharpening{: target="_blank" rel="noopener noreferrer nofollow"}.
Toothy vs Polished: Match the Finish to the Task
The finish that feels sharpest is not the finish that cuts best. A 600-1,000 grit edge leaves microscopic teeth that grab fibrous material. A 3,000+ edge pushes cleanly through firm material but slides on rope and cardboard.
| Task | Best finish | Why |
|---|---|---|
| Cardboard, rope, zip ties | 600-1,000 | Micro-teeth start the cut and keep slicing as they wear |
| Kitchen prep, soft food | 2,000-3,000 | Less friction, cleaner push cut, less tearing |
| Whittling, carving | 1,000-2,000 | Balances bite with control |
| Paper, tape, thin plastic film | 3,000+ | Polished apex glides instead of snagging |
| General EDC utility | 800-1,500 | Compromise: still toothy, still refined |
If you only own one finishing stone, a 1,000 is the safest choice for a knife that opens boxes and cuts tape: it leaves enough bite to keep working after the polish wears off.
How to Know You Are Actually Done at Each Grit
Three checks, all cheap:
- Light test. Shine a light along the edge at a low angle. A finished stage shows uniform scratch direction and no leftover coarse gouges. Scratches at 90 degrees to the last stage mean you skipped work.
- Burr check. Drag a fingertip across the edge (never along it). A raised burr feels like a wire. At each stage, raise a burr on one side, flip, raise it on the other, then remove it before moving on.
- Marker test. Color the bevel with a Sharpie, take three light strokes, and look. If the marker is only removed at the very edge, your angle is too steep for the existing bevel; if it is removed across the whole bevel, you are matching the factory geometry.
Angle consistency matters as much as grit. If the bevel angle shifts between stages, each new stone is cutting a different surface and the progression never converges. The angle guide for EDC knives covers which bevel angle suits which knife.
Grit Is Only One Third of the Result
Two other variables will undo a perfect grit ladder:
Pressure. Heavy pressure on a fine stone does two bad things: it crushes the abrasive and it flexes the apex. Use firm pressure on the coarse stage, light pressure on the apex stage, and feather-light pressure on any finish stage.
Flatness. A dished water stone only touches part of the edge, so you get a convex, inconsistent bevel. Flatten with a diamond plate before every session on soft stones; hard stones need it less often but still need it.
Angle discipline. A guided system removes this variable entirely; freehand sharpening does not. If your edges improve after a guided session and degrade after freehand, the grit numbers were never the problem. The sharpening systems comparison breaks down what each format is actually good at.
Matching Grit to Real Knives in the Catalog
Here is how the ladder applies to knives currently listed. Prices are catalog prices at the time of writing.
| Model | Steel | Handle | Sensible ladder | Catalog price |
|---|---|---|---|---|
| CJRB Lago J1926 | AR-RPM9 | G10 | 320 → 800 → 1,500 | $49.98 |
| Vosteed Porcupine | 14C28N | G10 | 320 → 1,000 → 2,000 | $69 |
| Kizer Sheepdog C01C 2.9 | Nitro-V | Micarta | 400 → 1,000 → 2,000 | $79.96 |
| Artisan Cutlery Tradition V2 1702M | S35VN | G10 | 400 → 1,000 → 2,000 | $89.99 |
| CJRB Tundra J1966 | D2 | G10 | 400 → 1,000 → 2,000 | $69.99 |
| CJRB Pyrite-Light J1945 | S90V | FRN | 600 → 1,000 → 2,000 | $79.99 |
| Kizer Feist 2 X Series | M390 | Titanium | 600 → 1,000 → 3,000 | $169.95 |
Two practical notes from that table. The AR-RPM9 and 14C28N knives are the easiest to learn on: they cut fast, they burr predictably, and a 320 stone fixes most mistakes. The S90V and M390 knives are the ones that punish a soft, dished stone, because the abrasive dulls before the steel does.
Once the edge is finished, a few passes on loaded leather realigns the apex without removing steel. That step is covered in knife edge stropping, and it is the cheapest way to extend the life of whatever grit you stopped at.
FAQ
What grit should a beginner start with? A 400-grit stone plus a 1,000-grit stone. That pair handles dull edges and light repairs on any of the budget stainless steels, and it leaves an edge with enough bite to be useful.
Is a higher grit always better? No. Above roughly 3,000, gains in push cutting are small and losses in slicing bite are real. Most working knives are better served by a clean 800-1,000 edge than a mirror polish.
How many strokes per grit? Stop counting strokes and watch the scratch pattern instead. The stage ends when the previous grit's scratches are gone and the burr is uniform, which is usually 10-30 passes per side depending on steel and stone.
Does grit matter for serrated edges? Yes, but differently. Serrated knives are sharpened on the scalloped side with a rod or round stone, and the grit determines how aggressive each scallop stays. Coarser is usually better here.
Why does my knife dull faster after a polished edge? A fully polished edge has less bite, so it slides on fibrous material and the user compensates with more pressure. That pressure plus the thin, polished apex is what dulls it quickly.