Whetstone Grit Guide

For kitchen knives, a grit around 1000 is the workhorse that actually sharpens a dull edge, and a finer grit of 3000–6000 refines and polishes it. That two-stone pairing covers almost every home cook. You only need a coarse stone (under 400) to repair chips or reset a badly neglected edge, and grits above 8000 are refinements a working kitchen edge simply does not require.

What the grit number means

A whetstone’s grit number describes the size of the abrasive particles bonded into it. A low number means large, coarse particles that cut metal quickly and leave deep scratches; a high number means fine particles that remove very little metal and leave a smooth, polished surface. Sharpening is really just controlled scratching — a coarse stone grinds a new edge fast but rough, and progressively finer stones refine those scratches into a keen, clean edge. That is why sharpening is a progression from lower to higher grit rather than a single step, and why the order you use the stones in matters as much as the numbers themselves.

JIS vs ANSI: why the number needs context

Here is the catch: a grit number only means something once you know which standard the maker used, and there is more than one. Most quality Japanese water stones are rated on the JIS scale (Japanese Industrial Standard). Many stones sold in North America use ANSI/CAMI grading instead. The two scales assign different numbers to the same physical particle size, so they are not directly comparable — a “1000-grit” stone on one scale is not necessarily the same fineness as a “1000-grit” stone on the other. In practice, stay within one brand or one standard when you build a progression, and treat grit numbers as a guide rather than an exact cross-brand measurement. The good news is that for kitchen knives, most reputable stones use JIS, so the common “1000 then 6000” language lines up across the stones you are likely to buy.

The grit bands

It helps to think in four broad bands rather than exact numbers:

• Coarse (under ~400):for repair only — removing chips, fixing a damaged edge, or re-profiling a very dull or neglected knife. Coarse stones remove metal fast, so you reach for them rarely and briefly.
• Medium (~800–1200):the main event. This is where sharpening actually happens — a 1000-grit stone sets a fresh, genuinely sharp edge on a normally dull kitchen knife. If you own only one stone, it lives in this band.
• Fine (~3000–8000): for refining and polishing an edge that is already sharp. It smooths the scratches left by the medium stone into a keener, cleaner edge that glides rather than bites.
• Very high (above ~8000):mostly for straight razors and enthusiasts chasing a mirror polish. For a working kitchen knife it is overkill — you will not notice the difference on an onion.

The practical progression for a kitchen knife

Most home cooks need just two grits. Start on a 1000 to establish the edge, then move to a finer stone to refine it. Two common pairings:

• 1000 then 6000:the classic combination, giving a refined, polished edge. A 1000/6000 combination stone — two grits bonded back to back in one block — is the single most popular choice, and for good reason.
• 1000 then 3000:a slightly more “toothy” finish that many cooks prefer for the way it grips food, and one fewer step of polishing to worry about.

Either is excellent. If you only ever buy one stone, buy a 1000/6000 combination and you are set for routine kitchen sharpening.

When do you actually need a coarse stone?

Rarely. A coarse stone under 400 grit is a repair tool, not a sharpening tool. Reach for it only when a knife is genuinely damaged — a chipped edge, a rolled tip, or a blade so neglected that a 1000 would take forever to raise a burr. For a knife you sharpen regularly, a coarse stone will only remove metal you did not need to lose, shortening the blade’s life. Skip it until a knife actually needs rescuing, and even then use it only long enough to fix the damage before moving up to the 1000.

Why “higher grit equals sharper” is a myth

It is the most common misunderstanding in sharpening. A knife taken to 1000 grit is already very sharp — sharp enough to slice paper cleanly and breeze through a tomato. Going higher does not make the edge “sharper” so much as smoother: it polishes the edge and its scratch pattern, which can feel keener and glide more cleanly, but the fundamental sharpness — how fine the very apex of the edge is — is mostly set by the time you finish the medium stone. A mirror-polished 8000-grit edge looks impressive, yet a working kitchen knife does not need a mirror; it needs a well-formed apex and a cleanly-removed burr. Chasing ever-higher grit past the point of diminishing returns is effort spent on looks, not performance. Put that effort into a consistent angle and clean deburring instead — those matter far more than the last few thousand points of grit.

Where to go next

Ready to choose a stone? Our best whetstones roundup compares specific stones by grit, material and prep, and our how to sharpen a knife walkthrough shows you how to use these grits in order, from soaking the stone to removing the final burr.