Keurig Slim Vs Mini

This is my comparison of the Keurig K Slim vs Keurig K Mini, two Keurig coffee machines that were specifically designed for people with limited countertop space.

I own the Keurig K Mini Plus, a very similar machine to the Keurig K Mini, and spent a whole day researching the Mini and Slim online to put together this comparison.

I’ll be comparing how the two machines fare along five parameters:

  • Quality of the coffee they make
  • Ease of use
  • Ease of cleaning
  • Size and aesthetics
  • What users of each machine say

Let’s get started.

Should I Buy the Keurig Slim or the Keurig Mini (Quick Verdict)?

The Keurig K Mini is a better coffee machine than the Slim if you want to make coffee using standard K cups. This is because the Mini allows you to make 6 oz coffees, which is the serving size that K cups were designed for. 

Any coffee over 6 oz brewed from standard K cups will be watery because the coffee-to-water ratio is too low.

If you want to make larger coffees using the My K Cup Universal Reusable pods, then the Keurig Slim is a better choice due to its use of multistream technology. 

The Keurig Slim is also better for office use due to its ease of use and ability to make multiple cups of coffee quickly.

Keurig K Mini Pros
  • Brews the better coffee with standard K cups
  • More flexibility with serving sizes than Slim
  • Most compact Keurig machine
  • Comes in a wide range of colors
  • Better for home use than Slim
Keurig K Slim Pros
  • Brews better coffee when used with reusable K cups
  • Faster and more quiet machine than Mini
  • Stores water in reservoir for later use
  • Better for office use than Mini

Overview of Products

The table below shows how the two products vary from each other:

AttributeKeurig K SlimKeurig K Mini
Dimensions (height, width, depth)12.14 inches x 4.76 inches x 15.20 inches12.10 inches x 4.50 inches x 11.30 inches
Maximum lid-up height17.28 inches16.80 inches
Mug clearance (with drip tray removed)6.00 inches (7.00 inches)6.00 inches (7.00 inches)
Available serving sizes8 oz, 10 oz, 12 oz6 oz – 12 oz
Reservoir capacity48 oz12 oz
Removable reservoirYesNo
Can its reservoir store water between brews?YesNo
Strong buttonNoNo
Multistream technologyYesNo
Altitude modeYesNo
Descale modeYesNo

The main differences between the Keurig K Slim and the Keurig K Mini are:

  • The Slim has a 48 oz removable reservoir at the back of the machine which stores water between brews. The Mini has a 12 oz reservoir that cannot be removed or store water between brews.
  • The Slim has preprogrammed serving sizes of 8 oz, 10 oz and 12 oz whereas the Mini just brews with whatever water you put in its reservoir. The Mini’s reservoir can hold 6 oz – 12 oz so serves coffee of these sizes.
  • The Keurig Slim uses multistream technology, meaning that it punctures K cups with five needles to allow for more efficiency and even brewing. The Keurig Mini punctures K cups with one needle at the top.
  • The Slim is 4 inches deeper than the Mini meaning that the Slim will jut out further forwards on your countertop.
  • The Slim has a more powerful heating element than the Mini, meaning that the Slim makes coffee more quickly and more quietly than the Mini.
  • The Mini comes in a wider range of colors than the Slim.

I’ll now go into a bit more detail on how these different features affect the quality and user-friendliness of these two machines.

Quality of Coffee

The Keurig K Mini makes better coffee than the Slim when you use standard K cups due to its ability to brew 6 oz serving sizes (the Slim cannot do this). 

The Keurig K Slim makes better coffee than the Mini when you use larger My K Cup Universal Reusable pods due to its use of multistream technology to achieve more through and more even coffee extraction.

The Keurig K Slim comes with a terrible design flaw in that the minimum amount of coffee that it brews is 8 oz. This means that the Keurig K Slim will always produce watery coffee when used with a standard K cup.

Standard K cups hold 0.36 ounces (10 grams) of coffee grounds. For filter coffee, the type that is made in Keurig machines, you want a coffee-to-water ratio of 1:16. 

This means that a standard K cup should ideally be used for a 5.76 oz coffee. You can brew a 6 oz coffee of decent strength with a standard K cup, but anything larger than this starts to become watery.

The Keurig K Mini makes a minimum serving size of 6 oz. This means that it can make a coffee of decent quality so long as you make a 6 oz serving.

Serving SizeAmount of coffee that you needCan the Keurig Slim create this coffee?Can the Keurig Mini create this coffee
6 oz0.36 ounces/ 10.5 gramsYes No
8 oz0.5 ounces/ 14 gramsYes, with a My K Cup Universal Removable podYes, but not as well as Slim
10 oz0.6 ounces/ 17 gramsYes, with a My K Cup Universal Removable podYes, but not as well as Slim
12 oz0.75 ounces/ 21 gramsYes, but wateryYes, but watery

The Keurig K Slim cannot make a strong, full-bodied coffee with a standard K cup. The Slim’s serving sizes are too big for the amount of grounds in the K cup.

Both the Keurig K Slim and Mini can take My K Cup Universal Reusable pods which hold up to 0.6 ounces (17 grams) of ground coffee. This is enough coffee to make an 8 oz coffee of decent strength.

The Keurig K Slim makes better coffees with My K Cup Universal Reusable pods than the Keurig K Mini.

This is because the Keurig K Slim uses multistream technology, puncturing the K cup with five needles at the top, rather than the Mini’s one needle). 

This causes more coffee to be extracted, and for extraction to be more even, in the Slim compared to the Mini resulting in a stronger, better-bodied coffee.

Winner: Draw

The machine that makes the better coffee out of the Mini and the Slim depends on how you make coffee. For bigger servings with the reusable K cup, the Slim wins out, however for smaller coffees with the standard K cup, the Slim is the way to go.

Ease of Use

The Keurig K Slim is an easier machine to use than the Keurig Mini. The Slim’s relative ease of use is down to a combination of its larger reservoir, its preprogrammed serving sizes and its superior heating unit.

The Keurig K Slim could not be easier to use. All the tricky parts such as measuring out water are done for you by the machine.

The Mini is slightly harder to use than the Slim because you have to measure the amount of water you need for each cup that you make. 

The Mini’s reservoir does have measurements on it, but these are not the easiest to read (see the image below). You’re therefore best off measuring out your water with a measuring jug.

The reservoir on the back of the Keurig Mini

With the Keurig K Mini, you have to wait about 90 seconds for the machine to heat the water before you can brew. 

The Slim has a better heating element, meaning that you only need to wait 30 seconds before you can brew. The higher quality build makes the Slim far quieter when brewing compared to the Mini.

The Slim will also make several cups of coffee in a row without needing to reheat the water. 

With the Mini, you need to fill the reservoir and wait around 90 seconds for the water to reheat each time. This makes the Mini far less suitable than the Slim for situations where you have to make several coffees quickly, such as in an office.

Winner: Keurig K Slim

The Keurig K Slim’s larger storage reservoir and better heating element make it much easier to use than the Mini. The Mini tries to maximise compactness at the expense of usability.

Ease of Cleaning

The Keurig K Mini requires less cleaning than the Slim. This is mainly due to the Slim’s multistream feature greatly increasing the frequency which you need to clean its K cup port holder.

There are three components of Keurig machines that need to be cleaned regularly. These are the reservoir, the K cup port, and descaling the inner pipes of the machine.

I’ll now go through how these two machines compare when it comes to the ease of cleaning each of these components.

Cleaning the Reservoir

All reservoirs on Keurig machines need to have their inner walls cleaned every 2-3 weeks as grime can build up in them quickly. The valves of the reservoirs should also be deep cleaned to prevent damage to the machine’s pump.

The inner walls of the Keurig K Slim’s reservoir are easy to clean as the reservoir is removable, so you can clean it in the sink as you would do with dishes. 

The Slim’s valve is quite tricky to clean, however, as it is at the bottom of the tall, thin reservoir. This makes it hard to get to the valve and still see what you are doing as your hand and arm block your eye-line.

Even though the Keurig K Mini’s reservoir cannot be detached from the machine, it is so shallow and wide that it is easy to clean both its inner walls and valve. The reservoir would be even easier to clean if it could detach, but taking a wet sponge to the machine and wiping it out is still hardly any effort.

Sponging down the Mini’s reservoir

Descaling the Machine

The two machines are descaled in the same way: by programming it to do a 12 oz brew with either descaling solution or vinegar in its reservoir and without any coffee in its port.

The Keurig K Slim tells you when it needs to be descaled. The descale button lights up, and when this happens it can only create 12 oz brews until it has been descaled.

The Keurig K Mini does not have such functionality. Instead, you need to remember to descale it. Keurig recommends that you descale their machines every three to six months.

The reminder to descale on the Keurig K Slim is a useful feature as the regularity that you need to descale a Keurig machine depends heavily on the mineral content of the water in your area. 

Failure to appreciate this can cause your machine to deteriorate faster, wasting your money in the process.

Cleaning the K Cup Port

Both machines have removable K cups that can be rinsed in the sink. The needles and crevices in the K cup port should be deep cleaned with a brush or a straightened-out paperclip and you should do this whenever you see coffee grounds on the needle.

K cup port removed from the Mini

When you take out the K cup port, you will likely see that the port holder has spilled coffee and grounds in it. This needs to be wiped clean as well because the coffee can go rancid.

Since the Keurig Slim punctures K cups with five holes, rather than one, far more coffee grounds and liquid coffee is spilled in the K cup port holder compared to the Slim

This greatly adds to the amount of time that you need to spend cleaning the machine and is a big negative for the Slim, in my opinion.

Ease of cleaning winner: Keurig K Mini

The Mini wins out here because the multistream technology used by Slim greatly increases the frequency that you need to clean its K cup port holder.

Size and Aesthetics

The Keurig K Mini is a more compact and more aesthetically pleasing machine than the Slim due to its wide range of colors. Many positive reviews of the Slim specifically praise its “cute” look.

The Mini and Slim have very similar (less than half an inch different) height and width, however, the Slim is about four inches deeper than the Mini.

This additional depth means that the slim is less suited for people with limited countertop space as the Slim can “jut out” and take up space used for food preparation.

Available Colors for the Keurig K Mini

Available Colors for the Keurig K Slim

Size and Aesthetics Winner: Keurig K Mini

The Mini wins this round as it is slightly more compact and comes in a wider range of colors than the Slim.

What Customers Say About the Keurig K Slim and Keurig K Mini

Both machines have over 40,000 reviews on Amazon and have an average rating of 4.6 stars out of 5.

Keurig K Slim

People who reviewed the Slim positively often mention its user-friendliness and high-quality heating system.

Example 1: “It takes almost no space up on the counter, I love this 5 inch wide size. Having the water reservoir is very convenient…I had considered some of the other models where you fill up each cup manually, but am glad I decided on this one, you can make several cups and not have to refill”

Example 2: “It has a reservoir which is so convenient and you can also pick your size 8, 10, or 12 Oz. It is also the quietest and fastest model I have ever owned BY FAR!”

Negative reviews of the Slim often centre around K cups bursting in the machine and the descale button being too sensitive.. 

Example 1: “It’s not brewing more than 4 oz and it blew up a pod, making a mess everywhere”

Example 2: “So disappointed. It constantly wants to descale, which we do after and properly. Won’t always brew the correct cup size and had even “blown the lid off” a k cup or two – which we always buy the Keurig brand of. “

You can read all Amazon reviews of the Keurig K Slim here.

Keurig K Mini

Positive reviews of the Keurig K Mini often mention its sleek look and range of colors.

Example 1: “I ordered this machine to replace the giant one I had before which finally died after years of use. I like this one a lot better because the color is prettier and it doesn’t take up so much counter space.”

Example 2: “Beautiful color. I like that it only does one cup at a time – saves space not having a water reservoir”

Negative reviews claim that the machine can be temperamental and inconsistent with the amount of water it dispenses.

Example 1: “It worked great initially. For about 3 weeks. Now it will only take in 2 ozs of water with each button push… so for an 8 oz cuppa java, you actually have to raise the handle up & down & push the button 4-5 times.”

Example 2: “This machine is very temperamental- some days it works, others it doesn’t. I am trying to return and get another model.”

You can read all the Amazon reviews of the Keurig K Mini here.

I got into more detail about this known issue of the Mini in my Keurig Mini review.

Final Verdict

Your decision to purchase either the Keurig K Mini or the Keurig K Slim depends on the size of coffee that you want from the machine, and whether you want to buy reusable K cups or not.

If you will primarily be drinking 6 oz coffees and brewing with standard K cups, then go for the Mini. The Slim cannot make 6 oz coffees.

If you want to make larger coffees of 8 oz – 10 oz and are happy to use My K Cup Universal Reusable pods for this, then the Slim is a better option as its use of multistream technology makes better coffee with this serving size.

f you’d like to find out more about either model, please see my Keurig Mini review or comparison of the Keurig Slim vs Mini Plus.