We considered the top brands recommended by expert and amateur reviewers alike. We focused on medium grinders in the 2-inch-diameter range—large enough to grind herbs for multiple sessions, but not so big they take up too much space—and looked for three- and four-piece models that let ground material fall through into a collection chamber. Letting gravity do the collection work is easier and less time-consuming than picking cannabis from between sharp teeth (as you would need to do when using a two-piece grinder).
On Amazon, best-selling and top-rated grinders that fit our initial criteria start at just $10, but seeing the difference between inexpensive grinders and models that cost up to $100 when shopping online can be difficult. Glossing over claims about sharper teeth or better materials when staring at pictures is easy, but the difference jumps out at you when you twist a quality grinder in your hands. It threads together with ease, plus glides and grinds more smoothly. We tested 12 models that ranged in price from $6 to $85 to determine the best value for most people based on four main criteria:
No binding when grinding: Some modern cannabis strains can produce flowers with incredibly dense buds that are hard to grind. The best grinders have teeth that will slice through these buds instead of binding while you try to force them through. The shape, sharpness, and number of teeth all contribute to this, but you can’t easily see what works best based on individual user reviews. During testing, we paid close attention to which design details resulted in easy, thorough grinds.
Easy to empty: A good three- or four-piece grinder should let most of your material fall through the holes between the teeth and into the collection chamber. It’s no fun to sit around picking tiny leafy chunks out from between sharp metal teeth. Yes, a knock or two will normally dislodge stuck buds, but sticky cannabis strains can stubbornly cling to tiny crevices. We looked for models that didn’t hold herbs hostage.
Evenness of grinds: Well-ground cannabis will often heat more evenly (and thus more efficiently) than uneven chunks torn by hand. Buzz at VaporizerWizard.com prefers to get a finer grind for conduction vaporizers, like models from the popular Pax line, or something a little coarser that lets air through for convection vaporizers like the Firefly. A slightly coarser grind is more flexible, though. To get a finer grind, all you need to do is give your flowers a few extra twists with the grinder upside down. That will keep it from falling through the holes into the collection tray and makes for finer material when you flip the grinder back over. Because preferences and uses vary, we focused on smooth and even grinds more than granularity in our testing.
Durability and support: A hunk of aluminum isn’t easy to damage, but accidents happen. Acrylic tops can crack and cross-threading two pieces when screwing them together can damage the threads. The pressure-fit and glued-in magnets that hold on the top grinding plate could pop out. Teeth can dull and begin to bind.
More teeth doesn’t always mean a smoother or faster grind. The shape and sharpness of the teeth determine the smoothness of the grind, and the size and shape of the pass-through holes contribute the how fine the final result turns out.
In short-term testing, we can’t replicate the type of use and abuse a grinder is likely to see over years of ownership. But in person and side by side, the varying construction quality is obvious. Some models felt cheap, made squeaks and groans when we unscrewed them, and had large, visible seams. The best models, though, felt precision-machined, with seams that disappeared from sight and would quietly glide across their threads. You can fairly assume that grinders made with care and precision should also last much longer. That said, we will monitor the performance of our picks over the long term.
If you’re going to spend more than the minimum to get a well-made grinder, having a company that will stand behind it is also nice. We noted the warranty and support options from each company, too.