Types of Grinders: 2, 3, 4 and 5 Piece Compared

Quick answer: Herb grinders are grouped by how many pieces they have. A 2 piece grinds and holds the herb in one chamber. A 3 piece adds a collection chamber. A 4 piece adds a screen and a kief catcher, and a 5 piece adds a storage jar. After that, the choices are teeth or toothless, the material and the size.

You go looking for a grinder and within about two minutes you're reading the words "4 piece, 63 mm, diamond teeth, anodized" as if any of that was obvious. It isn't, and most of it matters less than the listings make out. What does matter is pretty simple once somebody lays it out.

So that's what we'll do here. We'll go through the types of herb grinders by piece count first, because that's the big decision, and then the smaller ones: teeth or no teeth, what it's made of, how wide it is and how the lid closes. There's a table of our own grinders near the end if you just want to compare them side by side.

Types of Grinders by Piece Count

Nearly every handheld grinder is a stack of sections, and the name tells you how many. More pieces means more jobs done inside the grinder. It doesn't mean a better grind.

2 piece grinders

A 2 piece is a lid and a chamber, with teeth on both, and that's the whole thing. The herb stays in with the teeth, so you decide the grind by how long you twist. A few turns leaves it coarse and a dozen gets it fine.

There's almost nothing to go wrong, which is the appeal. No screen to clog and no bottom chamber to empty. What you don't get is anywhere to keep ground herb, or a kief catcher. Our 2 Piece Magnetic Grinder is 50 mm across with 33 triangular teeth, and the lid is held on by a magnet, so it opens with a pull and stays shut in a pocket.

3 piece grinders

A 3 piece adds a second chamber underneath. The floor of the grinding chamber has holes in it, and the herb drops through as soon as it's small enough. That gives you a more even grind than a 2 piece, because nothing gets ground twice.

Does a 3 piece catch kief? This is where the guides disagree, and it's because there are two designs. Most 3 piece grinders have holes and no screen, so the fine powder just lands in with the ground herb. A few put a screen in the bottom, and those do separate it. If kief matters to you, it's simpler to buy a 4 piece and be sure. We don't make a 3 piece, for what it's worth.

4 piece grinders

This is the one most people end up with. It's a lid, a grinding chamber, a collection chamber with a fine mesh screen for a floor, and a kief catcher at the bottom. Ground herb sits on the screen, and the finest powder sifts through and builds up underneath over a few weeks.

What do you give up? Really just height. A 4 piece is taller than a 2 piece, and there's a screen to keep clean. On the Premium 4 Piece EZ Grinder the screen lifts out, which takes most of the bother out of that. If you like the idea but want it smaller, the Mini 4 Piece EZ Grinder keeps all four pieces at 2.2 inches across.

5 piece grinders

So what's the fifth piece? It's a container. A 5 piece is a 4 piece with a sealed storage jar on the bottom, which means the grinder and the thing you carry your herb in stop being two separate objects. That's the entire case for one, and it's a good case if you take your grinder out of the house.

On our 5 Piece Storage Grinder the jar holds 3.5 grams and has an airtight lid with an O-ring seal. If you only ever grind at home next to a jar, you probably don't need the fifth piece, and we'd say so.

Teeth or No Teeth?

Most grinders cut with teeth, and you'll see a few shapes. Honestly, the shape matters less than how well the teeth are made, but each one does lean a certain way. Triangular teeth give a consistent medium-to-fine grind. Pyramid teeth bite earlier in the turn, so a full chamber goes through without you leaning on the lid, and the result comes out finer. Diamond-cut teeth are the pattern you'll see most often across the market.

Then there are grinders with no teeth at all. A toothless grinder has two plates with raised, petal-shaped ridges, and it mills the herb between them instead of cutting it. Nothing snags and nothing jams, and sticky herb mills much the same as dry. That last part is why people switch. Our 5 Piece Toothless Grinder works this way, and there's a longer comparison in our guide to toothless grinders.

Does the Type Change the Grind?

A little, yes. With a 2 piece you set the grind yourself, by how long you twist. With a 4 or 5 piece, the herb drops through the holes as soon as it's small enough, so it comes out about the same every time. As a rough guide, a medium grind is good for rolling, and a slightly coarser one works better in a pipe because it lets the air through. Finer isn't always better, by the way. Powder packs down tight and clogs the screen. There's more on getting it finer or coarser in our guide to using a grinder.

What Grinders Are Made Of

Aluminum is the standard, and for good reason. It's light, it doesn't dent easily, and teeth cut from it stay sharp. All of our metal grinders are aircraft-grade aluminum. Stainless steel is the heavier, pricier alternative, and you'll mostly find it at the top end of the market.

Acrylic and plastic grinders are the cheap ones. They're fine as a spare, but the teeth dull and snap, and the threads wear. We don't make them.

Wood looks better than anything else on this list, and the usual catch is softer teeth and a body that moves with the humidity. The way around that is to keep the wood on the outside. Our 2-Piece Walnut Grinder is solid walnut around an aluminum interior with 48 diamond-cut teeth, so the wood does the looking and the metal does the cutting.

And there's one more that most guides skip, which is plant-based. Our Plant-Based Hemp Grinder is made almost entirely of hemp, has 26 triangular teeth, and breaks down in about eight months in a compost facility. It's the least expensive grinder we make. You do need to keep it dry until you're done with it.

Herb Grinder Sizes

Size means the width across the top, and it's given in millimeters or inches depending on who's selling. It doesn't change how well a grinder cuts. It changes how much fits in one go and whether it'll sit in a pocket.

If you're not sure, go for the middle. A 2.5 inch grinder is big enough that you're not reloading it, and small enough to hold comfortably. A 63 mm grinder is a bit of a brick in a jacket pocket, though, so if it's going out with you every day, look at the 2 to 2.2 inch ones.

Magnets, Threads and Quarter Turns

Hardly anybody mentions how the lid closes, and it's the part you deal with every single time. There are three ways to do it.

Threads are the old way. The sections screw together, which holds well until residue gets in and binds them, and that's how grinders get stuck. A magnet in the lid is simpler. It closes with a click, opens with a pull and stays shut in a bag. A quarter-turn lock sits somewhere between the two. One short turn opens the grinding chamber and one locks it, whether the chamber's empty or packed.

Our aluminum grinders use magnets and quarter turns, and no long threads on the grinding chamber. If you've ever needed a rubber band to open a grinder, you'll know why.

Handheld, Electric and Card Grinders

Everything above is a handheld grinder, the kind you twist. There are two other kinds you'll come across.

Electric grinders do the twisting for you at the press of a button, which is useful for big batches. You get less control over the grind, there's a battery to charge and they cost more. Grinder cards are flat metal sheets about the size of a bank card, and they work like a cheese grater. They're a backup for a wallet and not much more. We only make handheld grinders, because for herb grinding by hand they're still the simplest tool for the job.

Which Type Should You Get?

It mostly comes down to where the grinder's going to live. If it lives in a pocket, get a 2 piece, or a mini 4 piece if you want the kief catcher as well. If it lives on a table at home, a full-size 4 piece is the one. If it travels with you and you'd rather not carry a jar too, that's what the 5 piece is for. And if your herb tends to be sticky, go toothless.

Here's our whole range in one place.

You can see them all in herb grinders. Once you've got one, our guides on how to use a grinder and how to clean a grinder cover the rest.

What You Can Ignore

A couple of things turn up on listings that aren't worth your attention. "Medical-grade aluminum" is one. It isn't a recognized grade, so it tells you nothing. A high piece count is another. Five pieces isn't an upgrade on four unless you'll actually use the jar. And don't pick a grinder on tooth shape alone. A well-cut tooth of any shape will beat a rough one, and you can usually tell which you've got the first time you twist it.

Types of Grinders FAQ

What are the different types of herb grinders?

The main types are 2 piece, 3 piece, 4 piece and 5 piece, named for the number of sections. A 2 piece grinds in one chamber. A 3 piece adds a collection chamber, a 4 piece adds a screen and a kief catcher, and a 5 piece adds a storage jar. Grinders also differ by teeth or toothless design, material and width.

What is the difference between a 2 piece and a 4 piece grinder?

A 2 piece is a lid and one chamber, so the herb stays in with the teeth and you control the grind by how long you twist. A 4 piece drops the ground herb onto a screen and collects kief in a bottom chamber. The 2 piece is smaller and simpler, and the 4 piece does more.

Does a 3 piece grinder catch kief?

Usually not. Most 3 piece grinders have holes between the two chambers and no screen, so the fine powder ends up mixed in with the ground herb. A few designs put a screen in the bottom section, and those do separate it. For a dedicated kief catcher, a 4 piece is the safer choice.

What is a 5 piece grinder?

A 5 piece grinder is a 4 piece with a sealed storage jar added to the bottom. The first four pieces are the lid, the grinding chamber, the screen and collection chamber, and the kief catcher. The fifth is a container, so you can carry ground or whole herb in the grinder itself.

What size herb grinder should you get?

For most people, 2.2 to 2.5 inches, which is 55 to 63 mm. That's big enough to grind a useful amount in one go and still comfortable to hold. Choose 2 inches or under for a pocket, and 3 inches or more if it stays at home and you grind larger batches.

What is the best material for a grinder?

Aluminum suits most people. It's light, strong, and teeth cut from it stay sharp. Stainless steel is heavier and costs more. Acrylic is cheap but wears quickly. Wood looks good and works best with a metal interior, and plant-based grinders are the lowest-cost option and can be composted.

What is a handheld herb grinder?

It's a grinder you work by hand, by twisting the lid against the base. Nearly all 2, 3, 4 and 5 piece grinders are handheld. The alternatives are electric grinders, which use a motor, and grinder cards, which are flat and work like a grater.

Are grinders smell proof?

Most aren't, because a grinder is made to cut and not to seal. A 5 piece grinder is the exception for the part that matters. Its storage jar has an airtight lid with an O-ring seal. For anything longer than a day or two, a dedicated airtight container does a better job.

Are these the same as the types of weed grinders?

Several customers report that our grinders work extremely well for that, but it isn't the intended use. ONGROK grinders are made for dry herbs. The types are the same whatever you're grinding: 2, 3, 4 and 5 piece, with teeth or without.

ONGROK products are not meant to be used for any illegal purpose.