Ratio vs. Simply Good: Which Plastic-Free Coffee Maker Is Best?

The era of plastic-free drip coffee has finally arrived. It couldn't come soon enough.

Drip coffee is my first true love when it comes to caffeine. But sadly, my first love is hopelessly addicted to plastic. From the very first Mr. Coffee machines in the 1970s, nearly every drip coffee maker on the market, including many of my favorite drip coffee makers, has included plastic at some point in the brewing process.

But plastic, as we're now learning, can leach tiny particles called microplastics into coffee or water, which you then happily drink in your morning cup. The science isn't all in on health risks, but it doesn't seem great.

Luckily, in the past year, a couple new machines have arrived with the promise to remove plastic from the equation: the Ratio Eight Series 2 ($799) and the Simply Good Coffee Plastic-Free Coffee Brewer ($480). Each promises to deliver delicious, high-end coffee without the plastic.

Each costs significantly more than machines made with injection-molded plastic parts that are easier to manufacture. And each has a couple quirks and trade-offs. But the Ratio Eight in particular makes drip coffee that rivals the best pour-over, and the best drip coffee I've ever tasted—and never brings hot water into contact with plastic.

But for those who want to avoid plastic completely, including on the cold water tank, there's really only one drip coffee maker I've tested that fits the bill: the Simply Good Coffee plastic-free brewer, which comes in at a much lower price.

If flavor is a primary consideration, I'd still recommend upgrading to the Ratio Eight. It's also the coffee maker that's become my daily driver when testing new coffee roasters and my favorite coffee subscriptions. But I understand that its price brings it out of reach for some. Here's the rundown.

The Fully Plastic-Free Machine: Simply Good Coffee

Simply Good Coffee is a fairly new name in the coffee world, founded in 2022 by former Bonavita CEO Laura Sommers. Until last year, it was also a reasonably obscure brand, devoted mostly to making more affordable takes on premium, precision coffee makers like the Bonavita and Moccamaster, whose design Simply Good Coffee somewhat resembles.

The plastic-free machine rocketed Simply Good into sudden prominence—and indeed, it's sold out its production runs more than once since its release last year, riding a wave of interest in plastic-free drip coffee makers. The design is similar to Simply Good's previous model, but with plastic parts removed from the equation.

The frame is made of 304 “food grade” stainless steel. The reservoir, carafe, and boiler tube are borosilicate glass. Certain connections, including the drip stop, are made with medical-grade, sand-based silicone fittings that are not thought to produce nanoparticles easily. It is, quite simply, the least plasticky drip coffee machine I am aware of. There's no plastic contact, hot or cold, and very minimal silicone contact.

Operation is dead simple. There are, in fact, just two switches. One turns on the brewer and the warming plate; the other controls the pour-over style “bloom” function, adding a small phase to wet the grounds before brewing a full batch. The machine will turn itself off after 40 minutes, or you can do so manually.

So how's the coffee? It's good. It's generally light-bodied, brewing in six minutes even on full 40-ounce batches. It's tested, but not certified, to maintain precise brewing temperatures throughout the entire brewing process. The results are better than most basic drip coffee makers, but don't quite keep pace with the best-of-the-best coffee makers: the Moccamasters, the Fellows, the Ratios. There's a coffee warmer, which I don't prefer, but many do.

Some parts aren't machined as precisely as I'd hope, leading to a little jiggle or awkward fits. And customer service is also a lesser-known quantity with Simply Good. Calls to the customer service center during business hours reached only AI operators. But I did receive a call back a couple days later from someone I believe to be human. And the replacement warranty is an excellent five years.

In the end, if you're buying this, you're buying it because, for now, it is the drip coffee maker that is the most dedicated to ensuring that your coffee maker isn't adding microplastics to your cup. If you filter your water for microplastics, the Simply Good Coffee will likely not add any microplastics after the fact. That's a lot of peace of mind.

Best Upgrade Plastic-Free Coffee Maker: Ratio Eight

The Ratio Eight Series 2 ($799) is a beautiful machine. Its brew basket and carafe are as hourglass-shaped as a 1960s movie bombshell. The machine is sleek-lined, walnut-trimmed. The stainless steel brew basket and even the lid to the reservoir arrive with pleasing heft.

The coffee that arrives from it is also artful. Ever since Portland-based Ratio released the original Ratio Eight in 2013, the company has been on the forefront of artful, aromatic drip coffee—drip coffee that can compete with pour-over as a vehicle for beautiful aromatics and flavor. Ratio previously certified all of its machines according to Specialty Coffee Association standards, and all are capable of maintaining excellent temperature precision.

But in some ways, Ratio has moved beyond the SCA, after testing extractions on batch after batch. Ratio brews a little longer and extracts a bit more fully—as long as nine minutes for a full 40-ounce batch, with a leisurely bloom cycle. The showerhead leads to admirably even wetting of coffee grounds and even extraction. The results are full body, round flavor, and a surprising wallop even from quite delicate beans.

Controls are as simple as whispering your hand across the device’s single button. Press longer, and the machine will optimize itself for half batch, its button glowing faintly and satisfyingly.

This excellent coffee flavor is also evident in the Ratio's other devices, whether the 40-ounce Ratio Six or the small-batch Ratio Four. Each of these is available for a much lower price than the Eight.

Aesthetics aside, the Eight's true reason for being is that it minimizes plastic contact. Neither hot water, nor hot coffee, ever comes into contact with plastic. The internal tubing is borosilicate glass. The pipe connectors are sand-based silicone. The chassis is stainless steel, and so is the brewing basket.

This does not mean it's plastic-free. Its cold-water reservoir is a BPA-free Tritan copolymer. The machine's frame is also made of polymer, a decision made for durability over and above painted stainless steel. There’s a bit of BPA-free plastic used in the heating element that doesn’t come into contact with hot water.

Some will not forgive that the reservoir is plastic, even as they might acknowledge it's nice not to have to worry about fragility. Contact time is minimal—and where coffee is concerned, leaching occurs almost entirely when hot water is in contact.

I privilege the beauty of the coffee and of the device. But for some, the plastic chassis and reservoir amount to too much polymer compromise. And while the device's operation is simple, note that the brew basket does steam up the top of the device, meaning you might want to wipe it with a dry cloth. Because there's no drip stop, the brew basket also comes with a little drip tray to place it on.

But as with all beauty, I accept the idiosyncrasies that come with it. In these weary times of plastic in my liver and gonads, this has become the drip coffee maker I use most often.

Affordable Plastic-Free Coffee Brewers

It is expensive and difficult—given the needs for tight valves and internal tubing—to make drip coffee machines and home espresso machines that are entirely plastic-free. But there are a few of WIRED's favorite, more affordable, and lower-tech options for those wishing to avoid plastic, if you're willing to put in a little effort.

WIRED consumer tech editor Michael Calore swears by the majesty of the flat-bottomed Kalita Wave 185 stainless steel coffee dripper for his morning pour-over. Just as I prefer a flat-bottomed brewing chamber for drip coffee courtesy of the Ratio Eight, the flat-bottomed Kalita Wave likewise leads to better-controlled and more even saturation of your coffee grounds. While a lot of pour-over drippers are plasticky, this one is not. And it still only costs $34. Just note that if you're getting into pour-over, you'll need a good gooseneck kettle like the rightfully ubiquitous Fellow Stagg EKG ($200).

A lot of modern French presses use plastic plungers or nylon mesh netting that's likely to sustain wear and leach out microplastics over time. Even worse, many modern French presses are entirely made out of plastic. Pish. Just get a stainless steel one. Maybe you won't get to stare longingly at your coffee while you wait, but it'll do the job. There are fancier stainless steel presses from Yeti ($110) and design-conscious brands like Aarke ($130). But this one from Secura is $40 and works great.

The AeroPress is an ingenious device, using pressure applied by hand to extract a smooth, rich, flavorful, aromatic cup of coffee through a paper filter at its bottom. The process, and the flavor, is somewhere between French press, filter drip, and espresso. But the AeroPress was a famously plasticky device for most of its lifespan. Lately, AeroPress is changing this. First, there was the Premium AeroPress (7/10, WIRED Recommends), which subbed in a fragile but beautiful glass tube for the usual plastic.

This year, AeroPress added a stainless steel coffee maker to the fold. It's not see-through, which means you'll need to measure your water and coffee by volume or weight rather than eyeball it. But that's what I do anyway. I appreciate that the brewing setup is 100 percent stainless steel. The plunger does contain a silicone liner, which will only have brief coffee contact for about 15 seconds.

This is not an easy question to answer, because scientific research is still in the early stages. The study of microplastics in the human body is new, and long-term studies still aren't in.

First things first: Coffee is likely not the biggest source of microplastics in your life. According to a study last year, hot coffee contains orders of magnitude fewer microplastics than water that's been bottled in cheap plastic. It also contains fewer than tea, because of nylon teabags. Depending where you live, you may have more to fear from your tapwater—and should first look into a good stainless steel water filter.

The general consensus, however, is that we should not welcome any additional tiny plastic particles in our digestive tracts and bloodstream, unless we need to.

Plastic is not very chemically reactive. But microplastics can transport other bad things into the body, such as bacteria. They can also just kinda … irritate your body. When they enter your bloodstream, they can reach vital organs and set off inflammatory responses and oxidative reactions.

Depending on the organ, this can do all sorts of stuff: imbalance hormones, mess with reproductive function, or even cause nervous system damage. Cancer, of course, is also a risk that's heightened by inflammation. Some reports show microplastics might weaken the immune system. Others that they may weaken the bones.

And so while coffee is not the worst risk where microplastics are concerned, caution is also not the worst approach.

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