Kitchen Composters I Recommend After 2 Years of Testing (2026)

Nov 6, 2026 6:30 AM

I Tested the Best Kitchen Composters, and Most Don’t Actually Make Compost

After years of grinding, drying, and fermenting my family’s food scraps, I’ve found the machines worthy of a spot in your kitchen.

Courtesy of Amazon

The countertop kitchen composter is a lovely thought. Instead of a smelly bucket of vegetable scraps and coffee grounds breeding fruit flies on your counter or attracting rats to your backyard, you could just put it all into a nifty electric gadget. Then, at some undetermined point in the future, you'll have a bountiful supply of nutrient-rich compost to use in your garden.

Unfortunately, none of the more popular electric kitchen composters do exactly this. Though some of these devices are marketed as “composters” and include instruction booklets and companion apps detailing the many ways to use compost, most will only grind up and dry your food scraps. You will greatly reduce your food waste output, and it will no longer smell, but if you’re hoping to put eggshells and banana peels into a machine and magically scoop out the kind of compost you’d buy at the garden center, that’s just not going to happen.

That said, you can mix small amounts of these grounds into potting soil in tiny ratios or use them as a feeder for a “real” compost pile. But again, most of these machines are meant for reducing the volume of household food waste. This is, itself, a legitimate goal, as cast-off food makes up an estimated 24 percent of municipal solid waste, resulting in the release of methane, a destructive greenhouse gas, as it breaks down in the landfill.

Or maybe you'd just like your food grounds to be odor-free and shelf-stable before adding them to your green waste bin for municipal composting or your backyard compost. In any case, despite critics’ cries of greenwashing and corporate astroturfing, there is indeed value to these devices. They make people more aware of their food waste. They don't use a huge amount of power (around 1 kilowatt-hour was typical in my testing). And my top pick, the Reencle Essential (8/10, WIRED Recommends), even produces something close to compost.

Also, be sure to check out our guides to the Best Indoor Gardening Systems and Best Smart Bird Feeders.

Updated November 2026: I’ve added Reencle's new Essential model as my new top pick, and ensured up-to-date links and prices.

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Featured Products

Best Overall

Reencle Essential Compact Electric Composter

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Also Great

Reencle Prime Electric Composter

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Best Grind-and-Dry Food Recycler

Lomi 3 Countertop Food Recycler

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Another Great Grind-and-Dry Recycler

FoodCycler Eco 3 Compact Kitchen Food Recycler

Read more

Best Overall

• Photograph: Kat Merck

• Photograph: Kat Merck

• Photograph: Kat Merck

Reencle

Essential Compact Electric Composter

As I mentioned above, none of these machines makes truly ready-to-use, biologically stable, fully decomposed compost, but Reencle comes closest to creating what you'd scoop out of a traditional compost bin or pile. Popular in South Korea years before it appeared in the US, Reencle machines arrive with a starter bag of Reencle Compost Starter (which you can purchase separately for $52) containing activated carbon, wood pellets, glucose, and a trio of patented thermophilic microbes ready to chow down. There's also a prefilled charcoal filter that slots into the back.

Cured Reencle grounds mixed with potting soil

Photograph: Kat Merck

The Essential is Reencle’s newest—and least expensive—model, with a refreshed, contemporary exterior; controls on the front instead of the top; and a lid that opens and closes manually. It's too large for a kitchen counter, but it conveniently operates much like a heated trash can. The lid opens via a manual button on the top of the unit, and in goes your organic matter. That's it. There are no cycles, tablets, or auxiliary buckets to worry about, and the cycle is barely louder than a refrigerator fan—about 28 decibels. Within hours to days, depending on the item, the scraps break down into a material resembling a cross between dirt and sawdust.

The smell isn't always pleasant, but you can usually mitigate this with the control panel's Dry and Purify buttons or by adding what, in composting lexicon, is called “browns”—dry, carbon-rich materials, like bread or shredded paper. The Reencle also tends not to stink when you feed it its preferred diet of 1.5 to 2.2 pounds of scraps per day. Unlike other machines, it can also accept meat and dairy.

When the volume reaches the fill line, it’s time to scoop out the grounds. At this point, you can mix the grounds with potting soil at a 1:4 ratio and leave it to cure for three weeks. (I used a large tub in my garage for this step.) Afterward, you can use it for both outdoor and indoor plants. I’ve used the resultant mix to positive effect both indoors and outdoors.

Dimensions	13.3 × 12 × 17.2 inches
Capacity:	Minimum 1.5 pounds, maximum 2.2 pounds
Can't process:	Large bones or shells, fruit pits
Cut food into small pieces before adding?	Yes
Fastest waste breakdown:	2 to 24 hours or longer, depending on the items
How to use its output:	Sift, mix 1:4 ratio with soil, cure for three weeks, and add to plants indoors or outdoors; add to compost pile
Warranty:	2 years

Also Great

Photograph: Kat Merck

Reencle

Prime Electric Composter

The Prime is Reencle’s original flagship model. It's pretty much identical to the new Essential, but with the controls on the top instead of on the front, plus a convenient sensor-activated auto-open and -close lid. The entire top also hinges open, making it easier to scoop out the grounds for curing. It's only about an inch taller than the Essential but accepts the same 2.2 pounds of kitchen scraps per day.

Inside the Reencle Prime

Photograph: Kat Merck

I found its fan noise to be slightly less intrusive than the Essential above, despite both units measuring at 28 decibels. It’s ultimately up to you if this, plus the auto-close lid, feels worthy of spending an extra $100. (I did like the latter feature very much.)

Also worth noting is that one of the stirring paddles broke off my Prime after a year and a half of daily use. I contacted Reencle to ask what customers should do in this situation. I learned that if the Reencle is within the warranty period (two years for units purchased on or after May 13, 2026; one year for units purchased previously), they can contact customer service to receive a paddle repair kit at no charge. If the unit is outside the warranty period, a kit runs $35. I don't love that this has happened, but Reencle's models remain the best of these devices available, and I've found the company's customer service to be responsive and easy to work with.

If you need a larger capacity: For larger households, there's also the Reencle Gravity ($649), which is Reencle's largest unit by both dimensions and capacity. It can accept 3.3 pounds of waste a day and sports the same convenient sensor-activated lid as the Prime. When I tested it last year, I found it to be significantly quieter than both the Prime and the Essential—not that either is noticeably loud, but the Gravity is nearly silent. I did, however, find that over time, the Gravity contents went anaerobic (read: smelly) much faster than with the Prime. The increased volume seemed to retain more moisture. If you go with a Gravity, I recommend keeping plenty of browns (old bread, shredded paper) on hand to maintain microbial balance or adding in a few more sessions of manual stirring per day with the included shovel.

Reencle Gravity (left) and Reencle Prime

Photograph: Kat Merck

Dimensions	12 x 13 x 18.4 inches
Capacity:	Maximum 2.2 pounds
Can't process:	Large bones or shells, fruit pits
Cut food into small pieces before adding?	Yes
Fastest waste breakdown:	2 to 24 hours or longer, depending on the items
How to use its output:	Sift, mix 1:4 ratio with soil, cure for three weeks, and add to plants indoors or outdoors; add to compost pile
Warranty:	2 years

Best Grind-and-Dry Food Recycler

• Photograph: Kat Merck

• Photograph: Kat Merck

• Photograph: Kat Merck

• Video: Kat Merck

Lomi

3 Countertop Food Recycler

Most kitchen “composters" simply grind and dry your food scraps, but the Lomi 3 countertop composter does the best job of this of the bunch. I'm always impressed when companies listen to feedback and adapt, and Lomi's most updated model solves a couple of the quirks found on the now-discontinued Lomi 2: Gone are the multiple modes, the annoying twist-off lid, and the need to put scraps right into the machine. Now there's a convenient 3-liter, 7.5-inch-tall countertop bucket, just like the FoodCycler below; an easy push-button lid; and Grow and Express modes. The Lomi 3 is also smaller and supposedly quieter than the Lomi 2, but my decibel meter found the difference to be negligible. One feature I did like on Lomi 2 that's missing from the 3, however, is Lomi mode, which could break down a list of approved bioplastics, including Lomi's own packaging. Lomi confirms the new model cannot accept bioplastics.

Lomi grounds

Photograph: Kat Merck

Like with the Lomi 2, there's a companion app for basic management, but I enjoyed not having to use it; simply press an on-device button, and the Lomi starts. When it's done (cycle lengths vary from three to 16 hours, depending on the amount and moisture level of its contents), it will play a little chime, and you can either put the processed grounds—which are very fine and look like Folgers—in your outdoor compost pile, top-dress your lawn with them, or add them to soil at a 1:10 ratio (1:15 if using meat or dairy). I also like that the Lomi 3 has a clear lid, so you can see exactly where it is in its cycle.

It's a lot to pay for what's essentially a grinder-and-dryer, which is why I generally recommend the Reencle above, especially if you want to generate something close to compost. However, for those simply looking to reduce their waste output, or who live in an area that's subject to composting fines, the Lomi 3 is a thoughtfully engineered, easy-to-use option.

Note that my test unit originally came with a lid that warped after several months, allowing odors to escape and attracting fruit flies. Lomi said the initial batch of lids was made with faulty plastic and sent a new lid, but the new version is starting to warp as well after a couple of months.

Dimensions	11 x 11 x 12 inches
Capacity:	3 liters
Can't process:	High-sugar products, hard bones, hard shells, sawdust, unpopped popcorn, compostable plastics
Cut food into small pieces before adding?	No
Fastest waste breakdown:	3 to 16 hours
How to use its output:	Mix with soil at 1:10 ratio, or 1:15 if using meat or dairy; add to compost; sprinkle on your lawn
Warranty:	1 year (two additional years of LomiCare are available as an add-on for $140)

Another Great Grind-and-Dry Recycler

Photograph: Kat Merck

FoodCycler

Eco 3 Compact Kitchen Food Recycler

First off, I appreciate that FoodCycler doesn’t even pretend it's making compost. “The FoodCycler is a food-waste recycler,” the company explained firmly before agreeing to ship a test unit. “Our primary goal is to provide a modern food-waste solution for users who may lack access to traditional composting or other disposal options that divert from the landfill. Therefore, the resulting byproduct cannot be labeled as ‘compost.’” And indeed, the FoodCycler breaks down food so quickly, and with no microbial involvement, that there’s no way anyone could think this was actual finished compost. But if you are opting for a grinder/dryer, know that the Eco 3 makes more groaning and creaking noises while in operation than the Lomi 3 above, but it is still a great pick.

Eco 3 grounds

Photograph: Kat Merck

Launched in 2024, the Eco 3 is a smaller version of the Vitamix FoodCycler FC-50 (7/10 WIRED Recommends), sporting a larger 3.5-liter capacity and, according to FoodCycler, better grinding capability. At 11 by 9 by 13 inches, it is small enough to sit on a counter or tabletop, though the real convenience with this machine is its auxiliary pail. Fill the sleek, 8-inch-tall lidded container with scraps (in my household of three people, this took about three days). Once it's full, swap out the lids, seat it in the machine, and press a button.

A few hours later, you'll have a handful of “Foodilizer,” a "homemade soil amendment” that looks like finely ground dirt, per FoodCycler. The output is among the most finely ground of any of these machines. There's no assembly (other than filling a filter with carbon granules), no app, no making an account, no pods or tablets or choosing various cycles—you don't even have to plug it in until you're ready to use it.

The cycle runs from four to nine hours, depending on the water content of the scraps. Though its base sound is an audible but unobtrusive whir (about 36 dB on my decibel meter), it has started making loud groaning and creaking sounds after six months of regular use, so I only run it at night or when I won't be home. I also occasionally had trouble getting the bucket to seat correctly, but the manual addresses this, and I figured it out after a couple of tries.

Note: If you know you like the FoodCycler, but you need a larger capacity, FoodCycler's XL Eco 5 model (see Also Tried, below) can accommodate 5 liters of kitchen waste with slightly larger dimensions (14 by 14 by 10 inches). WIRED reviewer Nena Farrell tested the Eco 5 during the holiday party season, but felt the required space made the smaller Eco 3 a better grind-and-dry processor.

Dimensions:	11 x 9 x 13 inches
Capacity:	3.5 liters
Can't process:	Compostable plastics, beef bones, candy, oils/fats
Cut food into small pieces before adding?	No
Fastest waste breakdown:	4 to 9 hours
How to use its output:	Mix with soil at 1:10 ratio, or 1:15 if using meat/dairy; add to compost; sprinkle on your lawn
Warranty:	3 years

A Decent Budget Grind-and-Dry Option

Photograph: Kat Merck

Airthereal

Revive R800 Kitchen Composter

Like many of these devices, the R800 is called a “composter,” but it does not compost, and this detail irks me. There's a “Bio Compost” mode where you can add Airthereal Revive Magic Compost Starter. This is not included, costs $30 on Airthereal's website, and simply adds thermophilic bacteria, akin to the Reencle above. This will get the process started, but the result will not yield anything close to fully decomposed compost. To even achieve pre-compost, you will still need to mix small amounts with large amounts of soil and then let it cure for weeks.

However, amid the landscape of grind-and-dry kitchen-scrap processors, the Airthereal isn't half bad for the price. It's not as seamless or slick as the Lomi or FoodCycler, but it will effectively reduce the volume of your kitchen scraps. There's also a digital screen on the front that tells you what's happening. I also like that you can see into the machine thanks to its clear lid.

Airthereal Revive grounds

Photograph: Kat Merck

The biggest detractor was the lack of a lid for the bucket. The bucket is intended to sit in the machine (where there’s no need for a lid), but after using these kinds of devices for more than two years, I've found it is much more convenient to have a bucket handy for scraps while you're working, instead of having to periodically go over to the machine and press a button with dirty hands. Airthereal does make a bucket-and-lid option for an extra $60.

The R800 isn’t obnoxiously loud during its grind cycle, at about 40 decibels, and while there is an app, it's not required to use the machine. The device requires a fairly large footprint, so don't expect to put it on your kitchen counter. Another note: Remember that the carbon filter is on the back and its location is not immediately obvious—you will need to remove it and its stickers before using the device, lest you run the risk of going on an errand and coming back to the house smelling like a dumpster in the hot sun. (Don't ask me how I know.) Some Amazon reviews mention issues with overheating and jamming, but I've been using the Airthereal off and on for a year and have never experienced any mechanical issues.

Dimensions:	14 x 12 x 14 inches
Capacity:	5 liters
Can't process:	Compostable plastics, beef bones, candy, oils, or fats
Cut food into small pieces before adding?	No
Fastest waste breakdown:	5 to 15 hours
How to use its output:	Not stated, but I recommend mixing with soil at 1:10 ratio, or 1:15 if using meat or dairy; add to compost; sprinkle on your lawn
Warranty:	1 year

Largest Capacity

Photograph: Kat Merck

Mill

Food Recycler

All of these machines do a great job breaking down food scraps in some way or another, but none fully address what to do with them, absent a yard or compost pile. Adding them at a 1:10 (or even 1:15!) ratio to potting soil is kind of a pain, and many people don't have the space to store all this dirt. The Mill is the only device that solves this issue by allowing users to ship their grounds in a box via USPS to a farm in Washington state that repurposes the broken-down scraps for chicken feed (for an extra fee).

When I first tested the Mill in 2024 (6/10 WIRED Recommends), I didn't care for this idea, which seemed inefficient at best and canceled out the benefit of recycling the food waste at worst. I also didn't love the coarse texture of the grounds, having tried to use them in my garden and finding them too easily rehydrated. The price also seemed over the top for what's essentially an oversized Lomi. But if you're looking to reduce the amount of food waste leaving your house, the Mill has the best ease of use, requiring the least amount of work on a user's part.

Mill grounds

Photograph: Kat Merck

Like the Reencle, it acts as a big trash can—you can throw in whatever you'd like at any time, and you can program a cycle any time you'd like via the app, which is exceedingly complete and user-friendly. There's an almost encyclopedic directory of what can and can't go in the machine, as well as a tracker that shows how many pounds of waste you've diverted over time. The Mill also has a massive capacity that only needs emptying about once a month—a claim I found to be accurate during my testing period. It's on the louder side at around 60 dB, so I highly recommend scheduling its processing cycle to run at night.

There are now two versions of the Mill: the Plus, which is the 27-inch version with a stylish wood-veneer top and lid-opening foot pedal that I tested, and the Essential, which is $200 cheaper, 4 inches shorter, and lacks the convenient foot pedal and wood-veneer finish. Both models have the same capacity.

Dimensions:	27 x 16 x 15 inches (Plus)
Capacity:	6.5 liters, or 40 pounds
Can't process:	Large bones or shells, large amounts of oil or sugar/candy, compostable plastics/packaging, moldy meat
Cut food into small pieces before adding?	No
Fastest waste breakdown:	3 hours to up to 24 hours
How to use its output:	Send in provided boxes to a farm, add to your own compost, feed to your chickens, add to soil at a ratio of 8 cups per 10 square feet
Warranty:	2 years, 2 additional years available for $199

The Analog OG

• Photograph: Kat Merck

• Photograph: Kat Merck

Bokashi Living

Bokashi Bin Starter Kit

In order to understand the intended purpose of electric composters, one first needs to know about the original indoor home composting method: the bokashi bin. Unlike traditional outdoor composting, which is straightforward anaerobic decomposition, the bokashi method, invented in Japan in the 1980s, is anaerobic fermentation. This method is a bit like quick-pickling your food waste to prep it for the decomposition process. The food scraps still need to decompose, but this gets it part of the way there with the least amount of hassle and time. In fact, some gardeners even prefer bokashi to compost, as the output retains nitrogen, a critical plant nutrient.

Bokashi “tea”

Photograph: Kat Merck

To start, put your food scraps in the included bucket, and once you have about a 1-inch layer of waste, add a sprinkling of microbe-infused bran (a 2-pound bag of bran with a little spouted measuring cup is included with the Bokashi Living kit). The instruction booklet for my Bokashi Bin also recommended putting a plate inside the bucket to push down the contents. Compost “tea,” or liquid byproduct of the fermentation process, can drain through a spigot on the bottom every couple of days and then be added to your outdoor plants. The smell is reminiscent of kombucha brewed in a hot dumpster with diapers and stale beer, so be sure to rinse out the cup each time.

Once your bin is full, let it sit for two weeks, and your food waste will have broken down enough to bury in your garden or add to your backyard compost. I admit I struggled with this part—after two weeks, my scraps looked much the same, only stinkier and slimier. Bokashi Living says on its website that this is normal: If it has a pickle-like smell and produces bokashi tea, it's a success.

I’ll admit it was refreshing at first to have a device that didn’t make noise, need maintenance, or use electricity, but a few weeks into testing the Bokashi Bin, I found myself sorely missing my Reencle. I didn’t keep a separate scrap bin on the countertop, so every time I needed to add refuse to the bucket, I had to peel the lid off with my dirty hands and remove the plate, which then made my hands even dirtier. The smell of fermenting food waste would then immediately—and as time went on, almost violently—permeate the kitchen and its vicinity. I certainly prefer any of the electric options listed above, but bokashi has its devoted adherents. If what I've detailed above doesn't sound bothersome to you, it may be worth a try.

Dimensions:	12 x 12 x 16 inches (approx.)
Capacity:	5 gallons
Can't process:	Large amounts of liquids, fat, grease, large bones or pits, excessively moldy food
Cut food into small pieces before adding?	Yes
Fastest waste breakdown:	2 weeks
How to use its output:	Bury in your garden or add to backyard compost
Warranty:	1 year

Compare Our Top 7 Kitchen Composters and Food Recyclers

Composter	Type	Fits on Counter?	Pros	Cons	Capacity
Reencle Essential ($349)	Microbiaal	No	Comes closest to producing actual compost. Quiet and simple to operate.	Push-button lid not as convenient as other Reencle’s sensors	14 liters
Reencle Prime ($449)	Microbial	No	Comes closest to producing actual compost. Convenient sensor-activated lid.	Stirring paddles may break off over time	14 liters
Lomi 3 ($449)	Grind-and-Dry	Yes	Best grind-and-dry performance. Convenient lidded scrap bucket.	Bucket lid may warp. Can no longer process compostable plastics.	3 liters
FoodCycler Eco 3 ($400)	Grind-and-Dry	Yes	Produces extra-fine grounds. Convenient lidded scrap bucket.	May develop creaking noises over time. Bucket is finicky to seat in the machine.	3.5 liters
Airthereal Revive R800 ($250)	Grind-and-Dry	Maybe	Affordable. Large capacity for a grind-and-dry machine.	No included scrap bucket. Less polished than competitors.	5 liters
Mill Food Recycler ($999)	Grind-and-Dry	No	Optional mail-in program for the output. Well-engineered and easy to use.	Very large and very pricey. Mail-in program is an add-on for price and carbon	6.5 liters
Bokashi Living Bokashi Bin ($83)	Anaerobic fermentation	Yes	Silent and uses no electricity. Very affordable.	Messy, hands-on process. Output is kind of gross.	5 gallons

Other Kitchen Composters I Tried

Clear Drop OC

Photograph: Kat Merck

Clear Drop Organics Collector (OC) for $399: From the makers of the innovative Soft Plastic Compactor, this simple white box does not claim to grind, process, or compost your food scraps; it simply stores up to 3.5 gallons' worth of them in an enclosed container with a fan and carbon filter for odor control. For its part, the OC did this well. I also appreciated the included paper-bag liners, which made it easy to drop off the scraps at a nearby collection bin, as my town does not have municipal compost. I also loved the sensor-activated lid that slides back and forth. Clear Drop posits that municipal composting is the best option overall for reducing waste via compost, because the process can be standardized for quality and is easy for everyone to comply. I agree, but let's be real: You can get a carbon-filter compost canister for less than $30. If taking the compost out every couple of days instead of every seven days is a chore you're willing to pay $400 to avoid, then knock yourself out. But you should know that the OC makes a loud fan noise—40 decibels on my decibel meter—which annoyed everyone in my household so much that I didn't even make it through the full test period.

Vego

Photograph: Kat Merck

Vego Countertop Kitchen Composter for $360: This grind-and-dry processor is roughly the same size as the Lomi, with many of the same operational features, but it is significantly less expensive. However, there are definitely some inconveniences that come with the lower price point. For one, you need to add scraps into the bucket while it’s seated in the machine. You can remove the bucket, but unlike with the FoodCycler, there's no separate lid for the bucket, and the metal mechanism underneath is exposed. Further, the machine’s lid is a bona fide pain to get on and off, requiring precise alignment of notches and two hands to wrench it open or closed. Needless to say, this is no easy feat with fists full of scraps. Vego claims its Vego mode does create a biologically active soil amendment when processed with one of the included VegoTabs (packet of 30, $30 if purchased separately). In all modes, but Vego mode especially, the barrel turns every couple of minutes, emitting a loud whirring. Because the sound isn't constant, it's more noticeable. Even from 10 feet away, I found it obtrusive enough to want to turn up the TV volume.

GEME Terra II for $700: Billed as the first “AI-powered kitchen appliance that uses industrial-grade microbes to turn waste into living soil,” this machine was the largest and bulkiest one I've tested (12 inches long, 22 inches high) and operates much like the Reencle, with a heated, enclosed container and a bag of proprietary starter microbes. Instead of a replaceable carbon filter, it uses a metal-ion purification system. Also similar to the Reencle, the GEME does not make ready-to-use compost but, rather, pre-compost that can be mixed with dirt. The role AI plays in this process is unclear: I couldn’t find an explanation on the website, on the machine itself, or in the instruction booklet. (GEME says it is working on an improved description.) The Terra II's signature feature is that its industrial-grade microbes can withstand the supposed high heat of the breakdown process. However, when I put a temperature probe into the Terra II's pre-compost after I'd had it running for about a week, it was 97 degrees Fahrenheit—nowhere near hot enough to kill pathogens. Further, during my testing period, this machine emitted a constant fan noise, like a range hood on medium speed—46 decibels on my decibel meter, which was loud enough to be disruptive.

FoodCycler Eco 5 for $500: Like the Eco 3 above, this is a food recycler and doesn’t claim to create true compost. It’s a large, quiet machine; my 3-year-old likes to turn it on when I’m not looking, and I don’t notice until I see that the blue light is on. The result doesn’t look like compost, but it does get ground down to some bare-bones food bits after several extra cycles my son initiates with his sneaky button-pushing. Each cycle runs between four and nine hours. It hasn’t been stinky, and I’ve found it handy to have nearby in the kitchen for food waste. It is quite large, though—nearly as bulky as my robot vacuum station due to its 5-liter capacity. The cheaper Eco 3 is likely a more efficient use of space in the kitchen, unless you have a ton of food scraps on a regular basis and really need the larger-capacity bin. —Nena Farrell

How I Tested

I cook daily for my family of three, and I've been processing our kitchen scraps in these composters in my home kitchen since the summer of 2024. I tested each machine under typical household use for a minimum of four weeks each, and in several cases, six weeks or longer. I tested all cycles offered, with all manner of foods allowed, according to each manual. I even attempted to use the finished product in my yard and potted plants (to varying effect). I acquired the units either by purchasing them myself or receiving them as samples from companies (with no expectation of coverage). When I completed testing, I donated or returned some units and kept others in office storage.

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Kat Merck is a commerce editor for WIRED, where she covers smart bird feeders, indoor gardening systems, kitchen composters, and all things sustainable home tech. As a forestry major at California Polytechnic State University, San Luis Obispo, Kat practiced axe throwing on her college logging team and trained as a wildland firefighter ... Read More