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Many coffee grinder models look suspiciously similar to spice grinders, and it makes sense. Both have essentially the same function: They take big things and make them smaller. But you’ve also probably heard your regular barista chirping in your ear to not use a spice grinder for your coffee. But why? Is there a difference between a coffee grinder and a spice grinder, and do you need a separate device for each function?

A Bit on Functionality

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It’s not a “one does this, and one does that” situation.

“The difference between a spice grinder and a coffee blade grinder is somewhat confusing, yet relatively simple,” says Julien Langevin, founder of Tomato Coffee Class and the 2022 United States Cup Tasters Champion (a competition where you have to taste sets of coffee cups and pick out the different one—a much more daunting task than you might think). “This is because electric spice grinders and coffee blade grinders are almost exactly the same.” 

So basically, if you drew a Venn diagram of spice and coffee grinders, in the middle would be a blade grinder. But in the other two sections, there would be lots of other tools. A pepper mill is a spice grinder, and that fancy espresso gadget you see spitting out ground coffee you see at your local cafe is a coffee grinder. But that thing in the middle of the Venn diagram—the blade grinder—is pretty much the same tool, whether you call it a spice grinder or a coffee grinder. 

“Coffee blade grinders use a single central blade to chop coffee beans into a fine powder, ready to brew,” Langevin says. “Most electric spice grinders actually use this same technique, and blade grinders like the Krups Coffee and Spice Grinder are sometimes marketed for use with both spices and coffee.” 

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Ok, so problem solved, right? You might think, “Let me just buy the one blade grinder, and I’m good to go.” Not so fast—while there are spice grinders and coffee grinders that have the same functionality, that doesn’t mean you should use this tool for your coffee and spice needs. 

What Does a Good Coffee Grinder Do? 

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Grinding coffee well is a critical step in the brewing process because coffee has such few ingredients: It’s just grounds and water, and the way you pull flavor from coffee depends a lot on how it’s ground. “Grinding coffee is critical to pulling the best flavor from coffee more efficiently because it exposes more of a coffee bean’s surface area to water,” says Alvin Kim, marketing manager for Baratza, a manufacturer of coffee and espresso grinders. “Can I use a spice grinder to achieve that goal? Sure. But will it taste good? Maybe, but not consistently.” 

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That’s because blade grinders (what Kim refers to above) chop coffee unevenly and inconsistently—there’s no formula for how long you should hold down the button on an electric blade grinder to get grounds for a specific brew method, and blade grinders offer no uniformity. 

“If you were to brew whole coffee beans it wouldn’t taste very good because the surface area of the bean is actually smaller than the sum of the surface area of all the little particles of ground coffee combined,” Langevin says. “The more surface area, the more coffee flavor is being pulled out of the bean.”

You might have whole beans floating around with finely ground coffee dust, which makes coffee extraction challenging: Imagine it like sauteeing an onion, except you took one half and chopped it up finely, and the other half you just threw in whole. “There’s virtually no way to control the grind size of a blade grinder,” Kim says. “If you’re very careful with how you grind, you absolutely can enjoy a decent cup of coffee from a blade grinder, but good luck repeating it.” 

Burr Grinders: Do I Need One? 

Instead, many coffee folks recommend burr grinders, which work to gently crush beans to achieve uniformity in grind size. “Burr grinders produce a much more uniform set of coffee grounds because they force beans between two cutting surfaces,” says Kim. “No coffee grounds can be larger than the space between the burrs, which means you can adjust the grind size for different brew methods simply by moving burrs closer together or further apart.” 

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However, it’s important to note that burr grinders are generally more expensive than blade grinders, and if your goal is simply to make better coffee, a blade grinder can be a good step in the right direction. “If your goal is to get away from pre-ground coffee to try more whole bean options at home, then purchasing a blade grinder seems like a fine option if that’s what works for your budget,” Langevin says. Coffee stales over time, and that process goes by even faster once you grind the coffee, so switching from pre-ground coffee to coffee ground at home—regardless of the grinder—will be a meaningful upgrade.

That being said, if you’re looking to improve your overall coffee game, the best place to start is with your grinder, and I’d encourage folks to look into a burr grinder before thinking about a fancy espresso machine or an expensive brewer. Coffee is a game of constants: To home in on finding out what you like, it’s helpful to set parameters and change only one variable at a time, and burr grinders give you that added level of control over grind size that a blade grinder can’t. “A grinder is to the coffee brewer as a lens is to a camera,” Kim explains. “It’s the critical, precise piece of the process that brings everything into clarity. With a good grinder, you’ll not only brew a more delicious cup, but you can also reliably repeat it.” 

Why It’s (Probably) Worth Having Multiple Grinders

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It depends on how dedicated you are to cleaning. Both coffee and spices leave residues when ground, so if you grind some coffee in your spice grinder, be prepared for your newly ground coffee to taste like spices

But you can clean those residues away. “For blade grinders, it’s suggested to grind a portion of raw white rice and then wipe with a damp paper towel to clean our spice or coffee residue. Some people even grind a slice of stale bread to soak up the flavors and oils,” says Langevin. 

In terms of using a burr grinder for spices, you’ll run into the same problems, and burr grinders are even trickier to clean—you usually have to take them apart or use a dedicated burr cleaner. I only have a burr grinder at home, and I would turn to a mortar and pestle first before thinking about running my spices through a burr grinder. 

There are so many options for both coffee and spice grinders, and you can choose how you want to equip your kitchen and coffee setup based on your needs and how often you’re grinding spices and coffee. A burr grinder for coffee, a pepper mill solely for peppercorns, and a mortar and pestle for every other spice works for me, but you can adjust based on your cooking and brewing habits. As long as you understand the limitations and capabilities of each item, you’ll be able to find the right tool that improves both your coffee and spice game. 

FAQs

Can a blender grind coffee beans? 

Technically, yes, but you’ll get even more inconsistency from a blender than a blade grinder since you’ll have grinds flying all around. The blades of a blender are also really difficult to clean, and you’ll face the same problems with cross-contamination (don’t make a smoothie in your blender after grinding coffee, unless you want a gritty, coffee-flavored strawberry banana smoothie!).

How fine should you grind coffee?

It depends! French press brewing usually requires a coarser grind, while espresso wants to be fine (and the finer your grind, the more difficult it is to get consistency in your grind—that’s why, generally, grinders designed for espresso are more expensive). 

Can you use a coffee grinder for spices? 

You can! There are no rules! But should you? Depends. I know I would forget that I ground a bunch of spices in my grinder and then make coffee the next day, only to be wildly confused about why I’m tasting cumin in my morning cup. Cross-contamination is real, and you do have to be pretty precise when you clean since fresh spices—and freshly ground coffee—are incredibly potent. 

Why We’re the Experts

Ashley Rodriguez is a coffee expert and writer who’s worked in the coffee industry since 2010. She regularly contributes coffee content to this site and has written several product reviews for us, including cold brew makers. For this story, Ashley spoke to Julien Langevin (founder of Tomato Coffee Class and the 2022 United States Cup Tasters Champion) and Alvin Kim (marketing manager for Baratza).

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