We Tested 8 Coffee Scales—Here Are The Best Ones for Accurate Brewing

We tested 8 different coffee scales to find out which ones were the best and had features that were helpful for manual brewing methods, like pourover.

the acacia pearl kitchen scale on a counter with a coffee grinder, pourover maker, plant and orange glass cup
Serious Eats / Jesse Raub

For coffee experts, using a scale is not just a suggestion: it’s a requirement. Like baking ingredients, coffee is a tricky one to nail down by volume. Different coffees have varying levels of density due to farming conditions and variety of coffee trees, meaning that standard, two tablespoon coffee scoops of two different coffees from neighboring farms in Colombia could have a 10% variance in weight. That’s important, because coffee brewing is all about extracting a percentage of the mass in order to achieve the sweetest and most balanced flavors. 

But coffee scales aren’t just for weighing out the coffee, they’re also essential for measuring the amount of brew water. In the early 2010s, single-cup brewing was becoming increasingly popular in most cafes and coffee bars. And as roasters began to offer more single-origin coffees in their lineup, demand went up. The more coffee bars tried to manage a row of pourover brewers, the more it became clear that it was extremely difficult to manage the consistency of water volume for multiple brews at a time. I experienced this first hand at a downtown Intelligentsia in 2010, when all of the fancy single-cup coffee machines broke down on the same day and we replaced them with 10 Hario V60 pourover brewers. Even though I was elbow-to-elbow with two World Barista Champions, all three of us were in the weeds trying to track how much water we were pouring into each cone.

When the idea to put your entire pourover rig onto a scale surfaced a few months later, it changed coffee brewing. Instead of weighing out coffee on a scale and measuring brew water by volume, you could now immediately track how much water was being added to the coffee in your filter. This created an immediate and accurate coffee-to-water ratio, which allowed for exponentially more accuracy and consistency from cup to cup. Not long after that, the coffee scale was born. In its most simple form, a coffee scale is designed to have a .1 gram resolution matched with a built-in timer, but some models have other features, too.

A number of coffee scales on a countertop
Serious Eats / Jesse Raub

But, why should you buy a coffee scale? I admit that for a lot people a kitchen scale is accurate enough to weigh out coffee. But kitchen scales aren’t up to the task when it comes to measuring out brew water. For starters, a lot of them aren't waterproof and some aren’t designed to withstand the heat of the brewed coffee on the weighing platform. And what's more: coffee scales can feature a flow rate indicator that helps you manage pouring speed and a built-in timer to aid in the whole brewing process. For those who love manual methods, like pourover and French press, these features are all mighty helpful for consistent, accurate brewing.

The Winners, at a Glance

The Best Overall Coffee Scale: Acaia Pearl


The Acaia Pearl is lightning fast, super accurate, and easy to use. On top of that, it also has Bluetooth functionality that expands its user interface, it can be re-calibrated, and it features a flow rate indicator to help people better manage their pouring speed.

The Best Budget-Friendly Coffee Scale: OXO BREW Precision Coffee Scale with Timer

The OXO food scale is Serious Eats top pick, and their coffee scale also delivers. With a large, easy-to-read display, simple interface, and accurate readings, the OXO Brew Precision Scale with Timer is well worth its $56 price tag. Out of all the non-Acaia scales tested, it also was the most accurate, yeilding quick readings for each pour.

The Tests

brewing coffee in a pourover brewer on the OXO scale
Serious Eats / Jesse Raub
  • Calibration Test: Each scale was tested with a 100-gram calibration weight to see how accurate it was.
  • Baseline Accurary Test: I placed a single coffee bean on each scale, to test for accuracy and its ability to register small amounts. 
  • Speed and Accuracy Test: I placed 10 coffee beans onto each scale and timed how long it took it to settle on a final weight. I also noted if this weight was accurate. 
  • Pourover Coffee Test: With each scale, I brewed pourover coffee, following these parameters and evaluating the scale’s ability to read brew water weight quickly and accurately. I also looked at the scale’s control panel: were the buttons responsive and did it manage weight and time simultaneously? 
  • Usability Tests: Throughout testing, I evaluated how easy each scale was to use and how simple its control panel was to read. If the scale had any extra features, like app connectivity and auto-ratio, I assessed those as well.

What We Learned

Most Scales Compensate for Low Weights

weighing a single coffee bean in a ramekin on the acaia pearl coffee scale.
While all of the scales struggled to note the weight of a single coffee bean, we don't really think this would be a common usage.Serious Eats / Jesse Raub

In our first accuracy test, I placed a single coffee bean onto each scale. Our control scale was an Acaia Lunar that had been calibrated with a 100-gram scientific weight and easily displayed that both a single coffee bean from Peru and a single coffee bean from Burundi weighed .2 grams. The Lunar is designed for accuracy (particularly when making espresso) with a smaller weight capacity and a highly responsive platform, but I didn’t expect to see that none of the other scales could even register a single coffee bean being placed onto their platforms. This was tested both with a zeroed out platform and a tared ramekin in order to test responsiveness with added weight, but the only clue as to what might be happening showed up on the Acaia Pearl S: with the Pearl S, the scale would quickly flash to .2 grams, then back to zero. When the coffee bean was removed, the scale would then read -.2 grams, showing that the scale had compensated for the light weight by re-zeroing its platform. Whether that means that the bulk of these scales just weren’t sensitive enough to read .2 grams or that .2 grams is a low enough weight that it’s within the scale’s margin of error, it’s hard to say. This test showed that none of these scales were up to the task for extremely lightweight readings, but I’m not sure many people are trying to weigh a single feather (or in this case, coffee bean) in their kitchen, either.

Design Was the Make-or-Break Feature

the acaia pearl with app open on phone next to it
Turns out: all of the scales were accurate enough for brewing.Serious Eats / Jesse Raub

With all my testing for responsiveness and accuracy, the reality is that all of these scales would function well for weighing out coffee and measuring water during brewing. Any accuracy issues were within a few tenths of a gram, and scales with slow response times still read fast enough for brewing. With that said, the best coffee scales just feel great to brew with, and had responsive weight readings that matched pour speed perfectly, and with buttons that were easy to locate and press even while holding a gooseneck kettle full of hot water. They also look sleek and modern, adding a touch of visual appeal to your brewing ritual. The worst performing scales were fine, but being tested next to some knockouts made them look and feel clunky and less pleasant to use.

Bonus Functions Were Often More Confusing Than Helpful

the brewista on a countertop with a finger reaching out and touching the mode button
Some of these scales, like the Brewista Ratio Scale, had extra functions and built-in brew guides, but we found these to be more confusing than helpful.Serious Eats / Jesse Raub

A few of the scales offered bonus programming features designed to help people learn how to brew. Ultimately, these features were confusing. Auto-tare functions meant the scale would re-zero itself mid-pour, auto-ratio functions made it hard to decipher how much water you were adding at times, and step-by-step brew guide functions required reading detailed guides to understand how to use them. While some people might find these extras helpful, they required extra effort and knowledge to use properly, and added more work.

Heat-Proofing Matters

A hand tapping the app of the Acacia Pearl S, which is beside the phone
All of the models tested had heat-proof silicone pads. Some of these were larger, some smaller—but every scale had one.Serious Eats / Jesse Raub

A key addition to every coffee scale is the inclusion of a heat-proof silicone pad. Digital scales use a load cell to measure weight, which converts the amount of pressure applied to the platform into an electronic signal that a scale displays as a weight. The load cells use electronic resistance (the measure of an object in opposition to the flow of its electric current) to calculate these measurements, and electronic resistance can be extremely sensitive to heat. One test I originally planned to perform was seeing how sensitive a scale was to having hot water in a glass vessel directly on top of it, but further research showed this could cause permanent damage to the scales. So, I accepted that all scales are likely sensitive to temperature. And, indeed, all scales I tested came with a heat-proof silicone pad in the box. 

The Criteria: What To Look for in a Coffee Scale

The Acacia Pearl scale with text points around it
Serious Eats / Jesse Raub / Grace Kelly

The best coffee scales are fast, responsive, intuitive, and have an easy-to-read interface. They give accurate readings instantly without any measurable delay, showcase a design that is water-resistant, and have a simple timer function that helps make brewing easier. Our favorite pick has a flow rate indicator that aids in manual brewing methods, like pourover.

The Best Overall Coffee Scale: Acaia Pearl

What we liked: The Acaia Pearl is lightning fast and accurate; it registered to .1 gram accuracy instantly, with no measurable delay. Other scales were off by .1 grams and took from a half-to a full- second to register. Its easy-to-read touchscreen is also extremely responsive, and has a few lights:  one that shows you if the scale is charging, one that flashes to show a button has been activated, and a flow rate indicator that helps you gauge pouring speed. There is a line of dots across the top of the display that starts in the middle and moves outwards to showcase just how heavy your pour is. If you’re just learning how to brew a pourover at home, this indicator is an easy, intuitive function that can help you with basic timing and pacing.

Aside from all of the display features, the Acaia Pearl also has bluetooth connectivity with an easy-to-use timer and tare functions, as well as the ability to adjust units of measure, toggle sounds, and even check on software and firmware updates. The app pairing does more than give a secondary read out: it also makes it possible to use the scale to easily weigh items that are wider than the platform itself, similar to a feature we loved on our winning kitchen scale.

What we didn’t like: The main drawback for the Acaia Pearl is the price. At nearly three times the cost of the runner up, the Acaia Pearl is a luxury item, even if the functionality and features are, in my opinion, worth the cost. Then there’s also the issue of the scale’s display. With a minimal design, it’s not totally intuitive which buttons do what when trying to reset the timer, reset the tare, and switch modes. Even though the scale’s manual is clear and the app interface makes it easy to navigate, others scales were more intuitive out of the box. Still, it’s hard to ignore just how much better the scale performed and how much more accurate it was.

Key Specs

  • Battery Life: 30-40 hours
  • Readability: .1 grams
  • Maximum Weight: 2000 grams
the acaia pearl scale on a granite countertop
Serious Eats / Jessie Raub

The Best Budget-Friendly Coffee Scale: OXO BREW Precision Coffee Scale with Timer


What we liked: The simplicity of the OXO made it a standout amongst the competition. While it wasn’t quite as responsive or accurate as some of the other scales during the coffee bean test, the OXO scale gave accurate water pour readings during brewing, and I appreciated its stripped down functionality and simple display. With a start/stop timer button on the left side of the scale, it was easy to control your timer while holding a kettle (at least, for right-handed people). We also liked the 3000-gram capacity which made it more useful for a wider variety of kitchen applications. Of all the scales tested, it was the most intuitive right out of the box and would be a great coffee scale for anyone looking to upgrade their set up at home.

What we didn’t like: The biggest downside of the OXO scale was its performance reading coffee weight. It generally took around one second to get an accurate reading, and even then it was generally off by .1 grams. It uses AAA batteries instead of a rechargeable internal battery, which might turn some people off from buying it.

Key Specs

  • Batteries: Four AAA batteries
  • Readability: .1 grams
  • Maximum Weight: 3000 grams
the oxo scale on a granite countertop
Serious Eats / Jesse Raub

The Competition

  • Acaia Pearl S: Hands down, the Acaia Pearl S was the most impressive scale for accuracy and responsiveness. It was the only scale that registered a single coffee bean, and the 3000-gram capacity made it stand out next to the Acaia Pearl. Ultimately, though, the higher price point and lack of flow meter on the display made it less appealing than the standard Pearl. The Pearl S also features Brewguide programming that walks you through custom recipes step by step, but this was a little too confusing. This is a pro-level scale, and would likely be more appreciated by a coffee professional. 
  • Timemore Black Mirror: The Timemore Black Mirror performed admirably in accuracy and responsiveness testing, but the smaller display combined with a cheaper overall feel kept it from being competitive. 
  • Hario V60 Scale: With a microscopic display and no backlighting, the Hario V60 scale was the hardest to read. It also didn’t even register any weight during the 10 bean test, calling into question its overall sensitivity levels.
  • Brewista Ratio Scale: The Brewista scale was a headache to use. With bonus ratio functions, a coffee mode and pouring mode, and unresponsive buttons, it was nearly impossible to use out of the box for simple weight and timer functions. It was also slow to read, and less accurate than most. 
  • KitchenTour Coffee Scale: The slowest, most inaccurate, and cheapest scale of the bunch, the KitchenTour scale just didn’t match the quality of the other scales.
  • Escali Versi Coffee Scale: The Escali Versi was almost the runner-up. It was nearly as accurate as the Acaia scales weighing coffee, had quick response times, and had a great form factor. The Versi was too sensitive during brewing, however, and the weight read out would fluctuate during pours. The timer button is also located on the right side of the scale, making it awkward to start and stop the timer while brewing with a kettle for right-handed people, but ideal for those who are left-handed.

FAQs

Is a coffee scale worth it?

People who brew by hand every morning with a French press or a pourover brewer would likely find a more streamlined process with a coffee scale. The added heat-proof silicone mats, the built in timers, and the accuracy of a good coffee scale can make manual coffee brewing much more accurate and consistent.

Do I need to weigh my coffee?

Different coffee beans will have different densities, so a two-tablespoon scoop of one coffee will not be the same mass as a two tablespoon scoop of another coffee. Coffee is the roasted seed of a small berry and higher elevation coffees are usually denser than lower elevation coffees. Once the berries are picked, washed, and roasted, two coffee beans side-by-side might look identical, but if one has 10% more mass than the other, a volume-based scoop will not represent the same amount of coffee. Scales measure weight, and give a more accurate representation of the mass of each coffee.

How accurate does a coffee scale need to be?

Coffee should be weighed out in grams due to the small quantity of beans most manual brew methods use. Because many coffee recipes are designed as a ratio of the weight of coffee to the weight of the brew water, measuring in grams is more accurate than measuring in ounces.  Most coffee ratios are one part coffee to sixteen parts water (1:16), and weighing both in grams can help with accuracy in brewing. The best coffee scales will show a .1 gram resolution so you know exactly how much coffee and water you’re using. It is also helpful to have .1 gram resolution when brewing one cup at a time, due to the smaller quantity of coffee being measured.

We Tested 6 Single-Serve Coffee Brewers—These Are the 2 We Recommend

We tested six, single-serving coffee brewers to find out which ones make the best coffee (one cup at a time) and which are the easiest to use.

The Aeropress with Fellow Prismo Attachment mid-brew
Serious Eats / Jesse Raub

Believe it or not, brewing one cup of coffee at a time is controversial amongst coffee professionals. “If the brewing method isn’t tailored to handle that amount of coffee, you don’t get quite the bed depth that you need and channeling is going to be a potential issue,” says Jaymie Lao, who has spent more than a decade in specialty coffee education. Her thoughts echo my own concerns. Essentially, if your bed depth of coffee isn’t deep enough, water has an easier time flowing unevenly through the coffee grounds, extracting good and bad flavors all at once. This means that even our favorite pourover brewers are not quite suited for brewing eight to 10 ounces at a time. Lao likes to brew closer to 12 ounces at a time, just slightly larger than the average coffee mug, and even adding just five grams of coffee to the bed depth can make a big difference. “The higher it is, the more you can observe the evenness of the coffee bed and make sure it’s level.” 

However, other coffee pros like to go small. “I pretty much only brew one cup at a time,” said Umeko Motoyoshi, owner of umeshiso.com. “I like to brew tiny cups of coffee because they are cute, and I also like to brew an amount that I can enjoy very quickly. If I brew a large batch then sometimes it can get cold and I’m not able to enjoy it all the way to the end.” I reached out to Motoyoshi for this piece because they were the first person I saw demonstrating the Fellow Prismo Attachment. “I love to brew with the Prismo attachment for the Aeropress. I have a different relationship to brewing a single cup of coffee because I’m making it just for me, or just for you, and it feels more special to me, and I pay closer attention to the brewing.” 

With the pros of brewing a single cup in mind, I set out to find the best manual coffee maker that can brew 8 to 10 ounces of coffee at a time, compiling a list of brewers that use pourover, immersion, and even pressurized brew processes. When searching for the best single-serve coffee makers, I intentionally left out the Keurig and other pod-based coffee machines. Aside from being expensive and creating more waste than brewing your own coffee, these types of machines are designed for convenience over quality, resulting in thin, bitter, and watery coffee—no matter what style of K-Cup or pod you purchase. (Editor’s note: Nespresso machines are another matter and we’ll have a review published on them soon.) I also did not include any espresso makers, as these were covered in their own review

The Winners, at a Glance

The Best Single-Cup Brewer: Kalita Wave 155 Dripper

I loved the Kalita Wave 155 Dripper for many of the same reasons its bigger sibling won our pourover brewers testing: the brewer’s simple flat-bottom design along with the size of the filter bed make it perfectly suited for brewing a single cup at a time. It can be paired with these filters and the Kalita 300-G server, if you don’t want to brew directly into your mug. 

The Best Single-Cup Brewer If You Like to Tinker: Aeropress with Fellow Prismo Attachment

While the Aeropress is a great brewer on its own, the Prismo attachment’s pressure actuated valve allows for even more control and customization. With a rubber stopper that stays closed until you press it, the Prismo allows the Aeropress to act as a full immersion brew method. Because the base of the Prismo is wider than most pourover brewers, we recommend the Fellow Mighty Small Glass Carafe to make sure there is enough clearance for the brewer.

The Tests

multiple single-serve coffee brewer on a grey surface
Serious Eats / Jesse Raub
  • Brewing Test: Each brewer was tested with an 8-ounce brew to assess bed depth, temperature stability, and brew time.
  • Each brew used 15 grams of coffee and used 250 grams water total.
  • Brew water was heated to 210ºF in an temperature-control electric kettle and then immediately used to start each brew cycle.
  • Pourover brewers had a 45-second bloom, and water was added in 25-50 gram pulses every 10-15 seconds.
  • Immersion brewers had all the water added at once, and were stirred for 10 seconds at the one-minute mark and allowed to steep five minutes.
  • The Aeropress was brewed inverted, and treated like an immersion-style brew with a two-minute, 45-second steep time.
  • The Prismo attachment was treated like an immersion style brew with a two-minute, 45-second time
  • Temperature Stability Test: Each brewer was tested for temperature stability throughout the brew cycle. 
  • Two waterproof probes from a Thermocouple were inserted in the coffee bed before brewing started.
  • The thermocouple recorded the temperature curve for the duration of the entire brew time.
  • Each brewer had its temperature assessed at the highest peak and heat loss was recorded during the entire brew cycle.
  • Taste Tests: Each brewer was then dialed in to produce the best tasting coffee.
  • Based on multiple brewing test, each brewer was assigned a custom brew ratio, grind size, and brew time to reflect the recipe that yielded the best results.
  • Each recipe was then adjusted to produce the best tasting coffee each brewer was capable of making.
  • Usability and Cleanup Tests: Each brewer was assessed in usability and design.
  • Brewers were evaluated on ease of use, picking up, filter attachment, handle comfort, and other tactile evaluations.
  • Brewers were evaluated on how easy they were to clean, including discarding of spent grounds and removal of coffee oils and residues.

What We Learned

Small Brews Lacked Thermal Mass

Thermocouple probes positioned in a pourover brewer
We tracked the temperature throughout brewing using a Thermocouple.Serious Eats / Jesse Raub

Across the board, these single-cup coffee brewers lost a lot of heat during the brew cycle. One of the main advantages of an automatic drip coffee maker is a closed brew basket and a boiler delivering water directly into the coffee bed. When I tested pourover devices, the full-sized devices couldn’t quite match the temperature stability of an automatic drip brewer…and single-cup brewers fared even worse. 

The ideal zone for coffee brewing is between 195-205ºF, and almost every single-cup brewer dropped below 190ºF before the brew cycle was finished, potentially leaving the coffee poorly extracted. This is because larger quantities of coffee in a filter contain more mass, and so do larger quantities of brew water: when brewing with only 15 grams of coffee and 250 grams of water, it was difficult for the coffee bed to hold onto heat.

Bed Depth Mattered

an overhead shot of the coffee brewing in the kalita wave 155
We found single-serve coffee brewers with narrower beds performed better.Serious Eats / Jesse Raub

It’s not a surprise that the best brewer in this review has the most narrow brew base. The Kalita Wave’s base was only five centimeters wide, while the Pure Over (one of the poorer performers) had a 10-centimeter diameter. With a narrower base, the small dose of coffee was able to create a deeper bed depth, which encouraged more even saturation, better flow restriction, and more consistent extraction overall. In comparison, the wide base of the Pure Over meant that coffee towards the edge of the brew bed dried out significantly earlier than coffee at the bottom of the filter disc, making it all but impossible to brew consistently at smaller volumes. 

Precision Was Key

a small amount of coffee beans on a scale
When brewing single-serving amounts of coffee, the margin of error is non-existent, which makes a coffee scale your best friend.Serious Eats / Jesse Raub

Shrinking down to a single-cup brew puts a microscope on the whole brewing process. If you’re off by a gram or two of coffee when brewing 60 grams of coffee and one-liter of water, the overall ratio of coffee to water remains more or less intact. But if you’re off by a gram when your desired dose is 15 grams of coffee? Your brew ratio is massively disrupted. 

The standard brew ratio for brewing is a 1:16.667 ratio of coffee to water: 1000g of water divided by 60 grams of coffee. Add a gram, and your ratio shifts to a 1:16.39 ratio. Add a gram to a 15-gram dose, and your 1:16.667 ratio drops to 1:15.625. Now, this seems finicky, but these ratios do matter! The lower the ratio of coffee to water, the stronger the brew gets, and the harder it becomes to extract the sweeter flavors you’re looking for. When brewing in the 8- to 10-ounce range, an extra coffee bean or two falling in the grinder, or an errant pour that adds a half-ounce of volume to your brew can throw the whole thing off. This is why, when brewing single-serve amounts, it’s very important to weigh everything in grams, even if you’re used to imperial measurements.

More Coffee Made a Big Difference

Water being added from a gooseneck kettle into an Aeropress
Tinkering with the brew is key to achieving a better, single-serve cup.Serious Eats / Jesse Raub

In our conversation, Lao highlighted the fact that five grams of coffee could make a huge impact in creating a more stable brew environment and coffee bed depth. None of the brewers really produced a stellar coffee at an 8-ounce volume, so in the second round of testing, I pushed the total brew volume as close to 10 ounces as I could, always brewing into the same mug to make sure it was never too full. With this larger amount, I found brew times were more consistent, and the brews themselves ended up tastier with a more balanced sweetness and body. At the end of the testing cycle, it’s hard to recommend anyone try brewing eight ounces of coffee—ever. 

The Criteria: What We Look for in a Single-Serve Coffee Brewer

A gooseneck kettle pouring water into the Kalita Wave 155.
Serious Eats / Jesse Raub

The best single-serve brewers were simple in design, easy to clean, had comfortable handles, and simply brewed great coffee in small volumes. They held onto brew temperature better than their competitors, and were more forgiving during the brewing process. A narrow base was also key to a well-functioning single-serve brewer: it encourage deeper coffee bed depth which in turn promotes a more even, better tasting extraction from the coffee.

The Best Single-Cup Brewer: Kalita Wave 155 Dripper


What we liked:The Kalita Wave 155 just simply brewed great-tasting coffee. With a flat-bottom design, the coffee was evenly distributed across the filter base which allowed the coffee to be saturated evenly during the pouring process. With such a narrow diameter, it was easy to maintain a coffee bed depth that allowed for even and consistent extraction, brew after brew. The short height of the brewer’s walls also made it easy for the spout of the kettle to get closer to the coffee bed, promoting higher brew temperatures. I also really appreciated that the brewer could feasibly brew up to 14 ounces of coffee, making it a more versatile brewer overall. Since the main body of the brewer is glass, the Kalita Wave 155 was easy to rinse off and wipe clean, with no coffee oils or residues left hanging on. With a base wide enough to rest easily on top of most mugs or glass servers, the Kalita Wave 155 is a utilitarian brewer. 

What we didn’t like: While the glass version is cheaper than the stainless steel version, it also felt significantly more fragile. The plastic base helped protect the glass bottom of the brewer from dense, stone countertops, but the base also felt cheap to the touch when compared to the brewer’s solid steel cousin. The handle on the glass version was rounded, which caused it to rotate slightly when picked up. 

Key Specs

  • Materials: Glass and plastic
  • Weight: 4 ounces
  • Surface Diameter: 5 centimeters
  • Base Diameter: 11 centimeters
  • Number of pieces: 2
  • Compatible with: Kalita Glass 300-G Server
Coffee brewing in the Kalita Wave 155
Serious Eats / Jesse Raub

The Best Single-Cup Brewer If You Like to Tinker: Aeropress with Fellow Prismo Attachment


What we liked: With the pressurized rubber value on the attachment’s base and a micromesh metal filter, the Prismo transforms the upright Aeropress into a full immersion chamber that lets coffee steep for as long as you’d like before pressing the coffee through the filter itself. The Aeropress with Prismo attachment actually brewed my favorite tasting cup out of all of the models — it just took some tinkering, and was not as repeatable as the Kalita Wave 155.

The Aeropress itself has a huge following due to its compact nature and the many ways to brew with it. (There’s even a yearly competition to see who can develop the best tasting coffee with an Aeropress, and custom recipes are highly encouraged.) One issue with the Aeropress, however, is that when brewing right side up, coffee tends to trickle through the filter because, well, gravity. This is pretty common when blooming any pourover brewer, but since the brewer only allows so much brew water to be used at one time, most people find the best results by inverting the brewer and turning it into an immersion chamber, with the stopper precariously holding the brewing coffee at bay. With the Prismo attachment, you can achieve the same full immersion chamber without the delicate and dangerous flip method. 

My favorite thing about the Prismo is truly how much more customization it adds to the Aeropress. My best tasting recipe with it used a slightly higher dose of coffee, which suits immersion brew methods, and a full 4-minute steep time before pressing down. Oh, and one more secret: even though the Prismo comes with a built-in metal filter, I added two of the standard Aeropress paper filters, which provided more resistance during the pressing period and helped filter out any lingering coffee grit. It’s the perfect set up for the coffee fan that loves to tinker. 

What we didn’t like: The Aeropress with Prismo attachment’s biggest strengths are also its biggest weaknesses: to get the best coffee, you have to tinker. With hundreds of different ways to set up a recipe, it can be difficult selecting which brewing bits and pieces you want to add into your own custom brew guide. It can also be tricky to properly seat a paper filter, if you want to go that route, and with a brewer that comes apart into four separate pieces, there are just a lot of moving parts to keep clean. Speaking of cleanup: puck removal from an Aeropress can be messy at times, as you have to unscrew the filter cap and press the grounds out. If you’re lucky, they’re fully compacted, but sometimes the grounds are loose and can spill all over. As the body of the Aeropress and Prismo are both plastic, they will tend to pick up more coffee oils and residues over time and will require deeper cleaning. And, lastly, this setup also requires you to buy two separate brewing devices. 

Key Specs (Together)

  • Materials: Plastic, rubber, metal
  • Weight: 8 ounces
  • Surface Diameter: 6 centimeters
  • Base Diameter: 9.5 centimeters
  • Length: 17 centimeters
  • Number of pieces: 2
The Aeropress and Fellow Prismo Attachment assembled and sitting on a scale
Serious Eats / Jesse Raub

The Competition

  • Aeropress: The Aeropress is a great brewer with lots of fun ways to brew but cup quality and usability is hard to match against an Aeropress with a Prismo attachment. It performed admirably at brewing small amounts of coffee, but had some temperature stability issues and required some tricky maneuvers.
  • OXO Brew Single-Serve Pourover Coffee Maker: The OXO Brew featured an auto-drip water tank designed to make pour-over more novice friendly, with measurements built-in. The issue is that water starts dripping through immediately, so if you’re trying to add exactly eight ounces to the reservoir, you likely have seen at least two ounces drip through already. The brewer is based off of the Melita cone shape, so the coffee bed can spread out wide along the bottom ride, but the auto-drip dispersion holes only let water drip in a narrow circle, leaving the edges of the coffee bed high and dry in comparison.
  • Espro Travel Press: Designed to be a French press on the go, the Espro travel press brewed some tasty coffee. The main issue, however, is the effectiveness of its dual wall vacuum construction. While it held the highest brew temperature out of all the single -cup brewers tested, it also held that temperature in what was now designed to be a drinking vessel. Unless you need a more compact French press for travel or camping, it’s likely you would have a better experience with a standard sized french press, since it has to be decanted anyways. 
  • Pure Over: Unfortunately, the Pure Over suffers from a massive design flaw: with such a wide and flat bottom that tapers to a narrow exit glass filter, the Pure Over creates an extremely shallow bed depth with a showerhead lid that is half the size of the base. This leads to an extremely uneven saturation of the coffee and guarantees channeling. The design of the brewer was just so flawed that I didn’t even move it to the second round of testing. On top of that, the brewer has a glass on top of glass on top of glass construction, and even included a ceramic coaster, which is all just begging for parts to chip and crack against each other. Plus, it was a pain to try and dump the coffee grounds and the straight handles on the pour over and mug were awkward to hold.

FAQs

What about Keurig or other K-Cup and pod coffee machines?

Single-pod machines tend to be very wasteful, but at their core, they’re just not good at making good-tasting coffee. Great drip coffee requires a standard ratio of coffee to water, a medium to mediu- fine grind, water temperatures between 195-205ºF, and a sustained brew time of around three to four minutes. Pod machines cheat these brew specs all in the name of convenience: there’s not enough coffee in the pods for the amount of water being used, so the coffee will be ground extra-fine, the machines will use boiling water to create pressure, and the brew times are forced too short. The end result is usually weak, bitter, and the method makes it impossible the match the quality of a freshly brewed coffee.

Can my drip coffee maker be used to make a single cup?

Some modern drip coffee makers have a single cup setting, but it’s not usually what that changes about the brew cycle. At the end of the day, the filter basket size on a drip coffee maker is designed for larger brews, so it would likely be difficult to achieve the right bed depth of coffee for a single cup on these machines. One option might be the OXO 8-cup coffee brewer, which actually features a smaller basket insert for brewing smaller volumes, though this basket is around the same size as the Kalita 185 brewer, and better designed for a minimum brew of 16 ounces. 

How much coffee should I use when making a single-cup pourover?

The standard ratio for coffee to water is 60 grams per liter of water, or 1:16.667 — that means you should start with one part coffee and about sixteen parts water. That could be one ounce of coffee and sixteen ounces of water, but measurements are much more accurate in grams when brewing smaller amounts. It’s also recommended to weight coffee out on a scale, and then place your whole pourover brew rig on the scale afterwards. This way, when you add water to the filter, you can measure exactly how much water you are adding to the grounds. An 8-ounce cup of coffee should use 15 grams of coffee and 250 grams of water added to it.