We Tested 11 Espresso Knock Boxes—Five Impressed Us

A knock box isn’t integral for making good espresso at home, but it keeps things efficient and tidier. Centered around a rubber-coated bar or pad, it's designed for knocking spent espresso pucks into a catch bin, resetting your portafilter basket for your next shot. It can be a huge timesaver if you make a lot of espresso at home.

Of course, espresso grounds are the bane of tidy counters everywhere, but so are drips from portafilter spouts. A great knock box catches it all and looks cute to boot. There are tons of different styles available, so we picked out 11 notable knock boxes to find which ones performed the best while looking nice and keeping your home coffee bar spotless. 

The Winners, at a Glance

The Best Espresso Knock Box

homeffect Knock Box

$26 $19 at Amazon

Though it may be simple to look at, the homeffect knock box has a unique knock-pad atop a column in place of a horizontal bar, giving it sturdy knockability in a lightweight package that was super easy to clean.

The Best-Looking Espresso Knock Box

Crema Coffee Products The Arc

$55 at Amazon View on Cremacoffeeproducts.com

With a swooping, tapered body and a walnut lid, The Arc was a welcome, stylish addition to our countertops. It also featured a removable knock bar for easy cleaning and a rubber base for shock absorption.

The Best Compact Espresso Knock Box

Dreamfarm Grindenstèin

$25 $20 at Amazon $25 at Food52 View on Seattlecoffeegear.com

Dreamfarm’s Grindenstèin has been a home espresso standby since it was launched in 2003. Its compact design and thick rubber bar are great at absorbing the shock of a solid puck-knock, and it’s small enough to fit on most espresso machines’ drip trays when not in use.

The Best Heavy-Duty Espresso Knock Box

Rattleware Bumper Knock Box

$80 at Amazon $70 at Seattlecoffeegear.com

Rattleware’s Bumper Knock Box has a commercial quality design used in coffee bars everywhere. It features an offset knock bar for cleaner knocks, a heavy-duty catchbin for durability, a rubber bumper that surrounds the catchbin for added shock absorption, and an attractive maple outer box.

The Best Espresso Knock Box, If You Have The Space

Dibsta Knock Box Drawer

$66 $52 at Amazon

Designed to sit underneath your espresso grinder, this drawer-style knock box also has cutouts on the top for easily sweeping loose grounds into the catch bin. We loved its usability, though it’s quite big: It was too tall to fit under kitchen cabinets with a grinder on top.

The Tests

• Standard Puck Knock Test: We pulled multiple shots of espresso and knocked the spent puck into each knock box, noting how easily the puck released, how sturdy and comfortable each knock box was to knock against, and how the design of each knock box affected its performance. 
• Baked-In Puck Knock Test: We pulled an espresso shot, let it dry out in the portafilter for ten minutes, and then knocked the spent puck into each knock box with an extra hard whack. We noted how easily the puck released, how sturdy the knock box felt with harder knocks, and how the design of each knock box affected its performance. 
• Usability and Clean-Up Tests: We put each knock box into regular use and evaluated how different design elements affected their ease of use, their ability to keep counters clean, and how easy it was to clean each knock box once they were filled with coffee grounds. 

What We Learned

Off-Center Bars Made Knocks Simpler

The best knock boxes had an off-center knock bar or knock pad to encourage the espresso pucks to fall directly into the bin. Knocking against a centered bar meant the puck would sometimes split, creating more of a mess in the catchbin. The knock bar on the Rattleware Bumper Knock Box is set around two-thirds of the way across the bin, making it easy to catch just the tip of the portafilter on the bar and let the puck fall straight down.

The knock pad on the homeffect Knock Box extends out from the front edge of the knock box, letting you tap just the back edge of the portafilter on the pad to eject your pucks forward. This made it easy to pop out pucks while catching stray grounds or drips from the portafilter and keeping pucks intact.

Thick Padding Added a Lot of Comfort and Stability

The thicker the rubber coating on the knock surface, the more comfortable it was to knock. We really loved how bouncy the bar on the Dreamfarm Grindenstèin and Dibtsa Knock Box Drawer were, but both models from Breville were lacking. With just a thin rubber coating, the knocks on the Breville Knock Box and Breville Knock Box Mini sent a lot of vibrations back to the wrist. The boxes also hopped on the counter with each knock. 

Wider Openings Kept Counters Cleaner

Narrow knock boxes, like the Solis Perfetta Knock Box, made a well-placed knock difficult and also didn’t catch errant drips or loose grounds as well. Wider openings, like on the Rattleware or the larger Breville models, made it easier to aim and kept counters cleaner. 

We also liked circular knock boxes, like the homeffect, Dreamfarm, and Crema models. By mirroring the shape of the portafilter basket, the round boxes provided extra space around the entire circumference of the basket for better cleanup. 

Some Designs Were Unexpectedly Sturdy

While thick rubber padding added to shock absorption, so did rubber feet and overall design. Surprisingly, the lightweight plastic homeffect knock box had the best shock absorption due to its rubber-coated knock pad and column. By situating the rubber pad on top of a vertical column instead of a horizontal bar, the entire impact is absorbed in the base. Even with more than 16 years of professional coffee experience, we’d never seen a design like this before. 

We wish we could say the same great things about the Saint Anthony Industries’ The Bloc, which also featured a knock pad, but the stainless steel bin it was attached to was flimsy and buckled under pressure, causing the knock box to wobble. 

Deeper Bins Were More Efficient

A home knock box doesn’t need the full capacity of a commercial model, but the Saint Anthony Industries model needed to be emptied after just two pucks. Dialing in an espresso grinder might take three to four shots before you nail the right setting, making this knock box really inconvenient. 

Deeper bins, like that of the Crema Coffee Products The Arc, held around eight to 10 shots, allowing you to dial in your grinder, pull yourself and a friend an espresso, and still not need to empty the bin. If a knock box’s main function is being a time saver, then a deeper catchbin is a requirement. 

Removable Bars Were Key for Quick Cleaning

Cleaning out a full knock box was easier when the bar was removable. Coffee grounds can get caught in the crease between the wall of the catchbin and the knock bar itself, and removable bars made this area easier to rinse off (as well as easier to empty the grounds). The Solis, homeffect, and Breville Mini all had removable bars that were easy to pop in and out. 

The homeffect knock box was actually the easiest to clean, however, as the entire catch bin in a single plastic surface with no corners or connectors. It was another example of how this unique design outperformed most traditional models. 

The Criteria: What to Look for in an Espresso Knock Box

The best knock boxes were comfortable yet sturdy to knock against with an off-center knocking platform. They featured wide openings that caught stray drips and grounds, and had a larger capacity, allowing for multiple espresso shots. They were also easy to clean when the pucks started piling up.

Our Favorite Espresso Knock Boxes

The Best Espresso Knock Box

homeffect Knock Box

$26 $19 at Amazon

What we liked: The knock pad/knock column design on this model is a truly unique approach to knock box design. It allowed for maximum shock absorption, which made it comfortable to knock against while staying firmly rooted to the counter, even with heavy whacks and stuck-in pucks. The fact that the knock platform is also off-center made each popped-out puck fall straight into the high-capacity bin below, and its raised sides caught any errant drips and loose grounds. 

What we didn’t like: The biggest downside is that this knock box just isn’t that attractive to look at. Knock boxes are part of home decor, and if you have a specific design taste you’re trying to match, this model might not cut it. 

Key Specs

• Dimensions: 4.5 x 4 inches
• Bar width: 4.5 inches
• Weight: 9 ounces 
• Materials: Plastic, rubber, stainless steel
• Care instructions: Dishwasher-safe (hand-washing recommended)
• Bonus features: Fits on drip tray, rubber stability base

The Best-Looking Espresso Knock Box

Crema Coffee Products The Arc

$55 at Amazon View on Cremacoffeeproducts.com

What we liked: With sleek, modern curves and a walnut lid, this knock box looks nice and performs well. We liked how the lid hid the splatters and pucks inside, as well as how it covered up most of the old coffee smell. Its vented edges let the pucks dry out, preventing mold from growing too quickly. It’s tall enough to hold a lot of coffee, and its removable bar rests on two notches instead of threading through the sides, leaving fewer crevices to be cleaned out. 

What we didn’t like: It’s pricey and narrow, and the knock bar doesn’t have as much padding as we’d like. That being said, it still performed well on knock tests (with a little concentrated aiming), and if looks are a priority, this knock box has ‘em. 

Key Specs

• Dimensions: 5 x 5 inches
• Bar width: 2 inches
• Weight: 7 ounces
• Materials: Plastic, rubber
• Care instructions: Dishwasher-safe (hand-wash wooden lid)
• Bonus features: Knock pad/column, rubber stability base
  

The Best Compact Espresso Knock Box

Dreamfarm Grindenstèin

$25 $20 at Amazon $25 at Food52 View on Seattlecoffeegear.com

What we liked: The Grindenstèin was the first product Dreamfarm ever made, debuting 20 years ago in 2003 as one of the first knock boxes designed for home use. And there’s a reason it’s remained popular: its squat design and heavy rubber padding on the knock bar make this compact model sturdy and great at shock absorption. It’s a simple design that’s small enough to fit on most drip trays when not in use, making it a great option for people with limited space. 

What we didn’t like: Because it’s so compact, the capacity is smaller than our other favorites. It’s also not the prettiest model out there. 

Key Specs

• Dimensions: 4.5 x 4 inches
• Bar width: 4.5 inches
• Weight: 9 ounces 
• Materials: Plastic, rubber, stainless steel
• Care instructions: Dishwasher-safe (hand-washing recommended)
• Bonus features: Fits on drip tray, rubber stability base
  

The Best Heavy-Duty Espresso Knock Box

Rattleware Bumper Knock Box

$80 at Amazon $70 at Seattlecoffeegear.com

What we liked: The bonus rubber bumper on this knock box added to overall shock absorption and reduced the need for accuracy. The catch bin itself was welded from thick stainless steel, and the sturdy knock bar had a thick rubber coating. Combined with a snug-fitting, solid maple outer box, it is one heavy-duty piece. This model is a favorite amongst commercial coffee bars and is designed to stand up to heavy use with a high capacity. If you’ve turned your kitchen into a coffee speakeasy for friends who drop by, this might be what you need to keep the line moving fast.

What we didn’t like: It’s a bit large for most counters, and it’s also expensive. People looking to save counter space or a few dollars might be better suited with one of our other picks. 

Key Specs

• Dimensions: 7.5 x 7 x 4.5 inches
• Bar width: 5.5 inches
• Weight: 3.5 pounds
• Materials: Wood, stainless steel, rubber
• Care instructions: Liner is dishwasher-safe, but hand-washing is recommended
• Bonus features: Rubber rim, removable liner, rubber feet
  

The Best Espresso Knock Box, If You Have The Space

Dibsta Knock Box Drawer

$66 $52 at Amazon

What we liked: The Dibtsa Knock Box Drawer is designed as a space saver by sitting underneath a grinder: the top is big and sturdy enough to support the weight of a commercial espresso grinder, and the knock bar lives in a high-capacity drawer that can hold at least 50 pucks, if not more. We liked how attractive the wood handle accent was, and the removable bar inside had a very thick coating for great shock absorption and comfort. The other detail we liked was the slits in the roof: stray espresso grounds are notorious for finding their way on the counter in front of a grinder, but with this knock drawer you could simply sweep them into the slits.

What we didn’t like: It’s expensive, and it's big. The drawer added height to each grinder, making it difficult to fit under kitchen cabinets. And at 12 inches, it was too long to fit on a separate coffee cabinet.

Key Specs

• Dimensions: 12.4 x 8.14 x 2.55 inches
• Bar width: 8 inches
• Weight: 6.5 pounds
• Materials: Stainless steel, plastic, rubber, wood
• Care instructions: Hand-wash only
• Bonus features: Drawer-style storage, high-capacity bin, grinder platform, slots for brushing grounds into
  

The Competition 

• Breville Knock Box Mini: This model was small and didn’t have enough padding: every knock sent it bouncing up off the counter.
• Breville Knock Box: This model was way too big and didn’t have enough padding: every knock sent a shockwave to our wrist.
• Kynano Knock Box: With an ill-fitting outer box, the catch bin wobbled around with each knock, making it uncomfortable to use. 
• Solis Perfetta Knock Box: Too narrow, and too many crevices: even with a removable bar and removable liner, coffee grounds made their way between the layers, requiring more cleanup. 
• Saint Anthony Industries The Bloc: While we liked the tamper caddy and the knock column, the catch bin was too flimsy and buckled under pressure. It also was the lowest capacity out of any knock box and required emptying after just two espresso pucks. 
• Lelit Knock Box: We liked this knock box, which featured a thick, rubber-coated base and bumper. However, while its bar was removable it had to be unscrewed and screwed back on. This didn't feel easy enough.

FAQs

What is a knock box used for?

A knock box is used for removing spent espresso pucks from the portafilter basket. Because espresso shots are pulled at nine bars of pressure (around 500 pounds of direct force), the spent pucks often become attached to the inside of the espresso basket and need a good solid whack to shake them free. The knock box has a padded surface to knock against and a catch bin to collect the spent pucks. 

Why do you need a coffee knock box?

A coffee knock box is great for two reasons: it allows you to swiftly clear out your espresso portafilter basket so you can pull your next shot quicker, and it collects your coffee grounds separately from your regular trash. Because coffee grounds are compostable, many people collect their espresso pucks for their backyard gardens or municipal composting. 

When should you clean your knock box?

Coffee grounds—even dried out pucks—still have a fair amount of moisture and are susceptible to mold growth. You should remove old pucks from your knock box every few days, and after emptying the grounds, fully clean your knock box to prevent any coffee residue from growing mold. 

Can you clean a knock box in the dishwasher?

It depends. Many of the knock boxes we tested claim to be dishwasher safe, but hand-washing is recommended for longevity. The materials matter, too. Knock boxes made with wood components (like the walnut lid on The Arc) must be hand-washed—and should never be submerged in water for prolonged periods.

Do knock boxes smell?

A knock box that hasn't been emptied for a few days will emit a stale coffee odor—but they're not as smelly as compost bins. Of course, a knock box with a lid, like the one from Crema, will mitigate smells.

Are espresso grounds compostable?

Coffee grounds can add nitrogen to a compost mix, but they need to be fully composted with other food scraps in order for their benefit to be fully realized. If you want to avoid tossing grounds into the trash, check if there's a local composting service that will collect and treat them for you.

Why We're the Experts

• Jesse Raub was previously Serious Eats' commerce writer. He spent over 15 years working in the specialty coffee industry. He's our in-house coffee expert and regularly tests coffee gear, including reviews of coffee roasters, coffee scales, and pour-over brewers. 
• For this review, he pulled and knocked out over 100 shots of espresso, testing their shock absorption, durability, and comfort.
• Crema Coffee Products’ The Arc is also featured in our Staff Spaces: A Former Coffee Pro's Home Cafe piece as the knock box he uses every day.