This post may contain affiliate links. Please read my disclosure for more info.
Without question, burr grinders are better than blade grinders. But which type of burr is the absolute best: flat or conical?
In this article, we set out to finally answer this question. We’ll compare all the traits of flat vs conical burr coffee grinders, including power, retention, noise level, and price. Our goal is to guide you to the exact right type of grinder for your needs, so let’s get to it.
What is the difference between a blade grinder and a burr grinder?
Before we jump in, let’s quickly recap the major types of coffee grinders: blade and burr grinders.
Blade grinders are relatively cheap and come in two types, manual and automatic. A blade grinder works by swirling coffee beans around and chopping them up into pieces, much like a food blender.
With a blade grinder, your beans come out very inconsistent. Some beans will be chopped to a fine powder while others end up in large chunks. The only control you have over the grind size is time: the longer you let it run, the finer the average particle size will be.
Burr coffee grinders, on the other hand, use fine cutting teeth, called burrs, which crush the coffee beans like a mill rather than cutting them like a blender.
With burrs, you can control the grind size by adjusting the distance between the burrs. Only grinds of a particular size can make it through, so you end up with a lot more consistency. This increased consistency and control is absolutely crucial when you are grinding your own coffee beans.
Flat vs Conical Burr Grinders: The Basics
A flat coffee grinder is one with two flat plates that sit atop one another. The beans drop between the two burr plates, which crush the beans until they are small enough to drop out vertically.
A flat burr grinder only needs to concern itself with grinding the beans in a parallel fashion. The burrs consist generally of two rings that lie flat from each other and are horizontally inclined.
Meanwhile, a conical coffee grinder has two cone-shaped plates, one large one with inward-facing burrs and a smaller one with outward-facing burrs. The beans fall between these two
The Pros and Cons of Flat and Conical Burrs
Many coffee experts believe that a flat burr coffee grinder will produce the very best in grind performance. This is based on the common wisdom that it’s easier to manufacture high-quality flat burrs as compared to high-quality conical burrs.
According to Marco Beltrame, a coffee trainer for Della Corte, a major coffee manufacturer, a flat burr grinder will produce an almost perfect grind day in and day out.
The problem with conical coffee grinders is that they are harder to manufacture correctly, so a flat burr coffee grinder produces a much more consistent fine grind.
So experts like Beltrame favor a flat burr coffee grinder, but is there more to the story? Yes, indeed.
Flat burrs grinders produce more heat
Since flat burr grinders take more power to work, they tend to heat up higher, particularly if you use them a lot.
This, of course, doesn’t really matter to most homebrewers as they are unlikely to be grinding more than a few dozen tablespoons of coffee a day. For coffee shops, though, that extra heat has the potential to burn the beans which will impact the flavor of the final brew.
Conical burr grinders waste fewer grounds
Good coffee is expensive, and you don’t want to waste it in the grinder. Plus when coffee grounds go stale in your grinder, they can impact the flavor and freshness of your coffee.
Due to how they are built, conical grinders leave much less waste than flat burr grinders on average. That’s why a lot of low-retention grinders, like the popular Baratza Sette 270, are conical grinders, not flat grinders.
Conical grinders are easier to clean
Because they retain fewer grounds, conical burr grinders are much easier to clean than flat burr grinders. You still need to clean your grinder regularly to avoid buildups of foul-tasting oils and maintenance issues, but conical grinders will remain cleaner between those cleanings.
Conical grinders are quieter
Flat burr grinders require a lot more force to ensure the beans are forced into the grinding chamber and then ejected out the sides. As a result, flat grinders have a tendency to produce a hair-raising whine from the motor.
Conical burs, on the other hand, tend to make for quieter coffee grinders. They require fewer revolutions per minute (RPMs) to do their work, so they can use less powerful motors. With less power comes less noise, which your roommates will certainly appreciate first thing in the morning.
Conical grinders are cheaper
With less powerful motors and simpler mechanical mechanisms, it’s possible to find high-quality conical coffee grinders that are about half the cost of quality flat burr grinders. That’s why most good budget coffee grinders are conical rather than flat.
Final Verdict: Flat vs Conical Burr Grinders
For budget and mid-range coffee grinders, it’s hard to beat conical burrs. That doesn’t necessarily hold for very high-priced grinders, especially in the industrial price range. But most of us won’t be shopping in that price range anytime soon.
I do want to stress that the difference between conical burr vs flat burr grinders is minimal compared to their advantage over blade grinders. Whether you want a French press coffee grinder or a grinder for your AeroPress, either type of burr grinder will probably suit your purposes. But if you want something cheap or you need a small coffee grinder for travel, you’ll probably find more conical grinders that meet your standards.