So today, I’m going to be telling you everything you need to know about that plus all the other essential information about coffee grinders’ RPM.
Having used coffee grinders for quite some time now, I know exactly how important the coffee grinder RPM is.
So join me as I reveal all on the matter. I’ll be discussing these key talking points today:
Let’s get started.
Coffee Grinder RPM Key Takeaways
The most important things to know about the RPM of a coffee grinder are that…
- A faster RPM is better suited to finer grinds
- Slow grinding means more uneven grinding
- A faster grind saves time
- Faster grinders are often more expensive
- Some believe that slow grinding ruins the taste
Fast vs. Slow Coffee Grinder RPM: Which One Should I Go For?
The RPM of a coffee grinder stands for ‘Revolutions Per Minute’. It refers to how many times the device turns within that period of time.
‘Fast’ would be considered as anything from around 1000 RPM over. But a slow grinder would be anything under 1000 RPM.
There are benefits to this figure being high or low. Here’s a look at a few of them:
- More convenient (grind is completed more quickly)
- Less heat is generated, which some people say helps the taste stay fresh*
- Keeps the coffee particles even, even when fine for espresso etc.
- Generally more expensive to buy a fast coffee grinder
- No good for coarse grinds as the particles will be too even
- More uneven coffee grind (good for coarse, bad for espresso)
- Less powerful grinders tend to be more affordable
- Easier to control the amount of time spent grinding
- Takes longer to complete the grind
- Uneven grind is no good for espresso
- Can generate heat, which could affect the taste*
*This feels like it should be the other way around, I know. But actually, slower grinding generates more heat because it lasts for longer . I have also always thought that the difference in the taste in coffee between a fast or a slow grind is negligible.
But the most important thing to base your grind speed decision on is which type of coffee you’re trying to grind. Let’s find out more about that.
You’ll also find something called ‘gear reduction’ in some low speed grinders. They have a fast motor that’s attached to gears, reducing the speed.
Faster grinders often have direct drive mechanisms where the motor is attached directly to the burrs and this keeps the speed as high as possible.
Coffee Drinks and their Recommended RPMs
As mentioned, different RPM speeds are better suited to different types of coffee drinks. Faster grinding means better particle distribution, leading to a more consistent grind size.
A slower grind will result in more distribution and this means the particles are uneven in size. This is great for coarse grind coffee drinks such as French press and filter coffee.
But a faster grind means that the particles will stay more uniform in size. That’s perfect for drinks like espresso and pour over.
Here’s a look at the general RPMs I’d recommend for each type of coffee drink.
|Suitable coffee types
|Up to 200 RPM
|French press, filter coffee, cold brew
|200 – 1000 RPM
|Pour over, moka pot, drip coffee, cold brew
|1000 – 3000 RPM
|Aeropress, espresso, pour over
|3000 RPM +
|Espresso and Turkish
This isn’t an exact science though. For example, you don’t need to be over 1000 RPM to get a good espresso grind. There are a lot of other factors at play, such as the quality of the blades or the burrs and more.
So, I wouldn’t worry too much about precisely getting your grind speed into one of the brackets in the table above. It’s generally just a good idea to be aiming in that direction.
Adaptable RPM Coffee Grinders vs Fixed RPM Coffee Grinders
You might not actually have much of a choice of grind speed if you already own a fixed RPM coffee grinder. These do not allow you to choose the RPM. Instead, they’ll be pre-configured to a particular speed.
If you don’t already own a coffee grinder, it’s worth considering which type of coffee drink you like to make the most before investing in a fixed RPM coffee grinder. For example, if you make a lot of espresso-based drinks, you’re probably going to want a pretty fast grinder.
Alternatively, you could buy a coffee grinder that has an adaptable RPM. Here, you’ll be able to change the grind speed in the settings although this feature is likely to cost you more money in most cases.
You can find out more about what to think about when you buy a new coffee grinder in this article.
Manual Coffee Grinder RPM: Is it a Factor?
The only type of coffee grinder we don’t need to look at the RPM is a manual one. With these, you’ll be turning the device yourself so there’s no way to preset the speed.
But, it’s still useful to know how fast you should be turning a hand coffee grinder when you do use one if you want to grind as fast as possible. I generally recommend aiming for a maximum of 100 turns per minute. But even that would be a bit of a physical stretch!
The RPM of a manual grinder doesn’t really affect the quality of the grind in the same way it does with an electric grinder because it’s going to be slow anyway.
It’s more important to grind it to the right amount time wise, and you can do this just by opening it every now and then and taking a look.
You can test your own RPM anyway by simply counting how many times you rotate the device in a minute (or scaling it down to 10 seconds and then multiplying by six).
Troubleshooting Coffee Grinder RPM Issues
Do you think that your electric coffee grinder isn’t grinding as fast as it should be? There could be an issue that’s causing this to happen. So, I recommend carrying out these troubleshooting steps.
Inspect the grinder for physical damage
There could be something broken within the grinder that’s causing it to act faulty. The first thing to check for in this case is physical damage to the machine’s exterior or interior.
So, have a good look around the outside of it and then take it apart to inspect the inside. How you do this depends on which coffee grinder you own, so if you’re not sure, just search online for ‘how to dismantle [your coffee grinder model]’.
Try a new mains output
Perhaps it’s a power issue that’s causing your issue. One way to troubleshoot this is simply to plug the grinder into a different wall output. If the issue persists after trying three or four different outputs, you can probably rule out an external issue.
Clean the grinder well
There might be a buildup of coffee residue or minerals from hard water that’s causing the motor or the burrs to slow down their grinding speed.
To avoid this from happening, it’s worth doing a deep clean. It’s also best practice to wipe down your coffee grinder every day or so, especially if you have hard water in your area and you use the grinder a lot.
If you want to find out about cleaning your coffee machine, I wrote an article about it that you can read here.
Speak to the manufacturer
Have you tried all these tips but the issue is still persisting? At this point, you’re probably going to want to speak to the manufacturer’s customer support team. They might be able to offer you some advice or more that could fix the issue.
Just search online for ‘[the manufacturer name] customer support’ and you should be able to find an email address, a phone number or something else that you can use to get hold of them.
If you’re within your warranty period and the manufacturer determines that it wasn’t your own neglect that caused the issue, they should repair or replace it for you free of charge.
Coffee Grinder RPM: FAQ
Check out a couple of extra bits of information that you might find useful about the RPM of coffee grinders below.
What is the faster coffee grinder RPM?
Some coffee grinders will rotate at tens of thousands of RPM! Personally, I think that’s overkill for most people, especially home users. Even if you want a great espresso, you probably won’t need anything faster than around 1500 RPM.
Any coffee grinder with an RPM over a few thousand is likely to be designed strictly for a professional setting for the highest output.
Are conical or flat burrs faster?
You’ll rarely find a conical burr grinder that has a faster RPM than 1500 RPM. However, flat burr coffee grinders that are designed for coffee shops etc can be up to 10x faster than this in some cases.
To find out more about the differences between conical and flat burr grinders, check out this article.
Last Thoughts on Coffee Grinder RPM
The speed of your coffee grinder affects the particle size of the ground coffee. And this directly affects how suitable it is for particular types of coffee drinks.
Fast coffee grinders are therefore better suited to espresso drinks, aeropress and pour over. Slower coffee grinders are going to be good for the likes of French press and filter coffee.
You might be able to buy a coffee grinder that has an adjustable speed but others come fixed And if your grinder is performing slower than you expect it to, this could be a sign of an issue.
So with all that in mind, you know all the important stuff about coffee grinder RPMs. Now, it could be time to learn a little more about the actual coffee drinks. You can read about those here.