Espresso Knock Boxes For The Home Barista
Discover the best espresso knock boxes on the market, tested by coffee professionals.
Ok, so you’re done with knocking your coffee grounds straight into the kitchen bin. While at the same time dripping espresso everywhere - I feel your pain.
A trusty espresso knock box is there to catch your used coffee grounds and keep your coffee station (and kitchen) crystal clean.
Albeit not the most exciting coffee equipment purchase.
An important one nevertheless.
Don’t make the mistake of buying a below par coffee knock box that isn’t robust enough to take a good old knocking or isn’t right for your coffee station.
Having worked in the coffee industry for over 10 years I have knocked my fair share of coffee grounds into knock tubes.
Here are some of our 7 favourite espresso knock boxes for your home and 1 to avoid.
| Best Espresso Knock Box | Brand/Model |
|---|---|
| Best Overall Espresso Knock Box | Sage - The Knock Box Mini |
| Best Budget Espresso Knock Box | APTSPADE - Coffee Knock Box Rubber |
| Best Professional Espresso Knock Box | Rhino - Thumpa Bench Knock Tube |
| Most Stylish Espresso Knock Box | Knock Out Box In Bamboo Surround |
| Best Compact Espresso Knock Box | Sage - The Knock Box Mini |
How to choose an espresso knock box?
Although they have very few moving parts like the espresso machine next door. There are a few things that you should be mindful of when purchasing a coffee knock box.
What size knock box should I buy?
Do you go for a small espresso knock box to fit almost unnoticeably next to your machine but have to empty it all the time or vice versa and have a kitchen bin sized knock tube on your work surface.
The truth is that even the smallest, most compact coffee knock boxes are sufficiently sized for the vast majority of home baristas.
Take for example our best compact espresso knock box below, the Sage Knock Box Mini. That holds roughly 20 shots worth of coffee grounds. So, providing you empty your coffee knock out box every few days this size should suffice.
How robust should the knock box be?
To be honest, I’m not known for my delicate touch. When I first started as a barista I really struggled to pull a decent shot and it was because I was tamping far too hard. Read our guide on coffee tampers
I have also managed to damage a few knock tubes in the past (mainly the rubber bar becoming cut up).
The nature of an espresso knock box is to be knocked so make sure the one you opt for isn’t fragile and I would advise as few moving parts as possible.
How easy is cleaning your knock box?
Keep in mind that you will be knocking moist coffee grounds into your coffee knock box which eventually will need cleaning.
Most espresso knock boxes on the market are easily cleaned and all of the parts are removable, but keep an eye out for cheap coffee knock boxes that look difficult to scrub.
How Do We Test Knock Boxes?
Top 7 Espresso Knock Boxes
Find below our favourite Espresso Knock Boxes. If you think we missed one, please leave a comment below.
1. Sage - The Knock Box Mini
Capacity: 1 Litre
Dimensions (cm): 10 x 10 x 11cm
Material: Plastic, Rubber, Stainless Steel Body.
Value: ★★★★★★★★★☆
Pros: ✅ Compact
Cons: ❌ Too small for some home baristas
The Sage coffee knock box mini ticks the most ‘knock’ boxes for us.
Sage are in our eyes the gold standard of domestic espresso machines, so as you would expect they have a pretty good espresso knock box available too.
Sage has a wonderful mantra - Listen. Obsess. Innovate. Test. Refine. Design.
Their products beat to the same rhythm and the Sage coffee Knock box is no exception.
Simple design, easy to use and robust enough for those with heavy hands (like me).
The coffee knock box is made out of a stainless steel canister that gives it that extra bit of durability.
The rubber bar makes the perfect material to really whack that portafilter against to absorb the blow but also fire the used espresso grounds into the box.
The bar is then detachable so you can easily clean the whole thing. It is otherwise locked in, which makes this knock box quite unique as many just rest on top of the box in grooves and can occasionally come loose and fall into the coffee grounds.
The base is also rubber which is anti-slip - even better for those heavy handed folks.
Lastly and most importantly for some the Sage coffee Knock box mini is a great compact size that doesn’t take up a great deal of space.
Although it doesn’t hold as much ground coffee as others it will still take around 20 used coffee pucks so unless you are smashing out a large number of coffee per day this is sufficient volume.
Does the Sage Espresso Knock Box tick all your boxes?
2. APTSPADE - Coffee Knock Box Rubber
Capacity: 1 Litre
Dimensions (cm): 12 x 12 x 10cm
Material: Plastic, Rubber.
Value: ★★★★★★★★★☆
Pros: ✅ Robust
Cons: ❌ Rubber bar can detach
The Artspade from Amazon is our best budget coffee knock box.
There are a number of similar products available on Amazon so you may find that this particular one isn’t quite right for you so take a look at some of the others.
The whole thing is made out of rubber and plastic.
These are great materials for an espresso knock box.
The rubber bar that you bash with your portafilter absorbs the impact while also creating enough resistance to knock out the grounds.
The rubber base is also a nice addition to hold it firmly in place so it doesn’t slip around your kitchen work surface.
Lastly, the way that the back of the coffee knock box is above the rubber bar which acts as a kind of splash shield for those shots that didn’t quite extract properly and you have an overly moist puck.
Is this coffee knock box exactly what you’re looking for?
On the lookout for a coffee machine, read about our best budget coffee machines.
3. Rhino - Thumpa Bench Knock Tube
Capacity: 11 Litre
Dimensions (cm): 30 x 22 x 22cm
Material: Plastic, Rubber
Value: ★★★★★★★★☆☆
Pros: ✅ Professional Volume
Cons: ❌ Large
If you are looking for a professional barista knock box then the Rhino thumpa bench knock tube is your ticket.
A knock tube rather than a knock box, this guy is the tabletop version of what you would normally see in a busy coffee shop.
Everything about this sort of cafe knock box is designed for professional use and volume.
It can be used in a small cafe/restaurant or office but also domestically if you happen to get through a lot of espresso coffee per day.
It is super robust and will take a good ‘knocking’ even by industry standards. All of the parts are detachable so it’s easy to empty and clean.
The large wrap around splash shield is also a nice element for the busy barista that can occasionally miss the bar and end up with coffee grounds over the other side of the knock tube.
If you’re looking for a professional knock tube then:
4. Stainless Steel Knock Out Box In Bamboo Surround
Capacity: 3.5 Litre
Dimensions (cm): 15 x 16 x 17cm
Material: Bamboo/Wood, Stainless Steel Insert.
Value: ★★★★★★★★★☆
Pros: ✅ Stylish,
Cons: ❌ Larger than most domestic knock boxes
If you are a rock star home barista and you pride yourself on your instagrammable coffee station then a bamboo/wooden coffee knock box could be just what you’re looking for.
Basically a simple stainless steel coffee knock box encased in a wooden or bamboo structure will keep your coffee game looking tight.
The espresso knock box is easy to use and very simply has a knock bar across the middle section. This whole structure is easily removed from the wooden structure for emptying and cleaning.
The wooden/bamboo structure doesn’t only serve as an aesthetically pleasing part of the coffee knock box, but also gives it a foundation so the whole thing doesn’t slip or damage your work surface.
One thing to look out for here is their size. If you only have a little bit of space to play with then maybe opt for a more compact espresso knock box.
If you’re into stylish coffee equipment:
5. Knock Out Drawer
Capacity: 5 Litre
Dimensions (cm): 34 x 24 x 8cm
Material: Stainless Steel Body, Plastic
Value: ★★★★★★★★★☆
Pros: ✅ Discrete
Cons: ❌ Moving parts can damage.
Espresso knock box drawers are completely different looking than their counterparts above and below.
These guys are made for the type of person that really doesn’t like mess and wants to be able to discard the grounds without having to see the remains.
Functionality: they usually open just like your underwear drawer. Simply open to reveal a knock bar, where you tap your portafilter into the tray and then elegantly close the door to hide the used coffee grounds like a knock box with a lid.
The tray is usually detachable so you can remove it to empty and clean, as is the knock bar.
Vents are strategically placed above on the top of the tray so the steam from the hot coffee grounds can escape.
One thing to think about and look out for with a coffee knock box drawer is they can sometimes break fairly easily.
The nature of moving parts compared to more solid coffee knock boxes is that the joints and brackets can easily bend with the force required to knock out espresso grinds.
6. Rhino - Deluxe Knock Box
Capacity: 3 Litre
Dimensions (cm): 17 x 17 x 17cm
Material: Rubber, Stainless Steel Body.
Value: ★★★★★★★★★☆
Pros: ✅ Solid
Cons: ❌ Slightly louder when knocking
The Rhino Deluxe knock box offer an in between option if you are looking for something that doesn’t have the plastic look and can withstand a bit of pressure.
The design is fairly standard and the functionality is very similar to other espresso knock boxes described above.
The body is made out of stainless steel but it sits on a rubber pad to add a little more stability and won’t slip away, it also means it is quieter than those with a steel bottom.
The knock bar is super robust.
Made from stainless steel also but has a rubber layer to softer the impact and sound.
That said it is a little louder than other coffee knock boxes that have bars made from plastic and rubber.
Does this espresso knock box sound like your cup of tea?
7. Steel Knock Box
Capacity: 2 Litres
Dimensions (cm): 9 x 17 x 13cm
Material: Rubber, Stainless Steel Body.
Value: ★★★★★★★★★☆
Pros: ✅ Simple
Cons: ❌ Bottom can slip
A very simple and no nonsense design. Why over complicate it?
A steel espresso knock box like the one above is a great choice for many. It is basically a solid steel tray with a knock bar attached along the middle.
They are normally the cheapest option on the market and are pretty robust.
A few things to keep in mind though if you are a no-nonsense home barista.
Firstly, they are not as easy to clean as others. The bar is usually fixed so you kind of have to clean around it or give it a good soak to remove all of the coffee grounds around the joints.
Secondly as it is made out of stainless steel (which is incredibly robust), it can slip around a little and if you’re one to give the knock bar a good old hammering then you may end up with a tray of coffee grounds skidding over your worksurface.
One To Avoid - Knock Chutes
A Knock chute is a type of espresso knock box that should be avoided for the majority of home baristas.
They are made as a knock bar to sit directly above a coffee grind bin but mounted onto the work surface.
You may come across these in a cafe or restaurant and are usually associated with somewhere with high volume.
They do look very similar to a coffee knock box, so it is quite easy to miss that they are not suitable for your kitchen.
The product should list that it is a chute rather than a box but take a look at the images and make sure that it’s a box rather than a box without a bottom.
FAQs
What is an espresso knock box?
An espresso knock box is essentially a coffee grind bin for used espresso grounds.
When you make an espresso, ground coffee is added to a portafilter basket. The coffee grounds are then tamped before being locked into the group head on the espresso machine. Water is then forced through the grounds extracting the delicious velvety espresso coffee.
But what happens then? Well before making another shot for your quadruple shot macchiato you need to empty the grounds.
A coffee knock out box, usually positioned to the right of the espresso machine has a bar running over an empty vessel. The portafilter is removed from the espresso machine and with a gentle whack (like hammering a nail) on the bar the grounds fall into the coffee grind bin and your basket is ready for another shot.
Why do you need a coffee knock box?
A coffee knock box is needed to dispose of your used coffee grounds after you have made an espresso and is usually conveniently placed next to the espresso machine so you can quickly make another shot without hurrying to the bin.
What is a good espresso knock box?
There are a number of factors that make a good knock box and they will all change according to the preferences of the user.
Any good knock box however should be robust and sturdy after all you are basically hitting it with a heavy portafilter after you make each coffee.
Other variables that may be taken into account are the size of the knock box, if you only have a small space to play with then a compact espresso knock box may be the better option.
Style can also be taken into account and may be influenced by the type of espresso machine you have.
How often should you empty an espresso knock box?
You should empty your espresso knock box as it starts to fill up and you are not able to knock any more grinds into the box.
Otherwise if you only use your espresso knock box sporadically make sure the coffee grounds (like any other organic waste) doesn’t start to rot and dispose of them accordingly.
How do you clean a coffee knock box?
Although there are variations in size, shape and material of espresso knock boxes they all require similar methods of cleaning.
Always hand wash and disassemble all of the parts (if that’s possible), give everything a good scrub with warm soapy water and towel dry.
How to make a homemade espresso knock box
Although I have never personally made a homemade coffee knock box I would imagine it isn’t too unachievable given you have the right tools.
To make a simple homemade espresso knock box you would need a square stainless steel container and a stainless steel tube. Attach the tube in the middle of the container by drilling two holes either side and then tape up the tube to give it a more cushioned knock.
Do knock boxes smell?
Knock boxes should not smell unless they haven’t been emptied for some time. Coffee grounds, albeit moist when they enter the knock box, don't tend to give off any bad smells. Make sure you empty the box as it starts to fill up and clean it every now and again.
