Shoes made from wood pulp that are actually comfortable? Count us in! Allbirds took the internet by storm after its Wool Runners, made using New Zealand merino wool and tested by numerous consumers, were deemed “the world’s most comfortable shoes” by almost everyone. After selling 1 million pairs of shoes just two years after officially launching in March 2016, the brand developed a cult following pursued by celebrities like Leonardo DiCaprio and former President Barack Obama. At $95 a pair (the company has yet to have a sale, citing the fact that it is already charging the lowest amount possible for its shoes), Allbirds can be enjoyed even by those without celebrity-level wealth.

aerial view of blue sneakers

Allbirds was founded in New Zealand, a place where sheep outnumber humans six to one. According to the company, its process uses 60 percent less energy than typical synthetic shoe manufacturing, and companies such as ZQ Merino make sure the wool used in these shoes is held to the highest standards of farming, land management and animal welfare.

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The newer Tree Runners line takes sustainability a step further — these shoes combine the time-tested merino wool with light tree fibers. Inhabitat tried out the Tree Runners for a couple of months to see if these captivating sneakers are all that they are cracked up to be.

feet in blue sneakers propped up on rock with city views below

Allbirds’ Tree Runners are made using sustainably harvested eucalyptus pulp. The material is lightweight, forms to your foot and helps your feet stay cool with its breezy fabric. The tree fiber, TENCEL™ Lyocell, is sourced from South African farms that rely on rainfall rather than irrigation and need less fertilizer. If you compare that to cotton, according to the site, it uses 95 percent less water and cuts the carbon footprint in half. The trees are FSC-certified as well, meaning the wood is harvested sustainably and held to a strict standard to protect forests. To create a signature yarn to meet its own standards for comfort and sustainability, Allbirds combined the eucalyptus tree fiber and merino wool for the unique Tree Runners.

The shoe laces are made entirely from post-consumer recycled polyester; the eyelets consist of bio-based TPU, which is formed by plant sugar-consuming microorganisms. For cushioning, Allbirds uses castor bean oil rather than petroleum-based foam to reduce carbon output.

cardboard shoebox that reads, "Allbirds"

So far, we’ve walked many steps in these shoes, including in a couple of cities in Europe, all across Disneyland and beyond. The results were happy feet and hardly any soreness — no easy feat when it comes to full days of non-stop walking. The shoes are great for the changing seasons and temperatures thanks to the breathable yet sturdy fabric, and they are easy to slip on and off at the airport.

One of the chief complaints among customers has to do with the sizing, which doesn’t include half-sizes, presumably to avoid wasting product because half-sizes are so minute. Allbirds combats this issue by assuring a 30-day, no-questions-asked return policy if its shoes don’t fit, suggesting buyers size up in the Wool Collection and size down with the Tree Runners and Tree Skippers if they typically wear a half-size. The shoes came packaged in imaginative, 90 percent post-consumer recycled cardboard that served as a combination shoe box and mailer all in one.

feet in blue sneakers standing on a ledge near a pond

Another factor that throws consumers off is the claim that the shoes can be comfortably worn without socks due to the breathable and soft merino wool, which minimizes odor (less sweat equals less stink). We wore them for short periods without socks and can say that they were perfectly comfortable, although after about an hour or so, there was slight rubbing on the back of the heel (no blisters to speak of, thankfully). Speaking of wool, don’t let that scare you; merino wool is some of the softest material on earth. It’s nothing like the scratchy wool sweaters your Grandma used to put you in.

Despite the name, these shoes don’t feel well-suited for long-distance running. The shoes are machine-washable, and the website sells replacement insoles for $15 each. While there was no issue with foot support on our end, those who need a lot of additional arch support may want to consider getting their own insole inserts.

feet in blue sneakers propped up on ledge near ocean

The company is so transparent about its manufacturing methods that you’d almost think they wanted others to steal their ideas (hint: they do). It is a mindful organization that clearly values the environment while still retaining a business model that keeps its sustainable ways in the public eye. Allbirds is also a Certified B Corporation, meaning that it is required to consider the impact of its business decisions on the environment.

Comfort aside — and these shoes are very comfortable — the focus on genuinely sustainable materials is the real triumph with Allbirds’ one-of-a-kind footwear, especially considering that, even in 2019, a vast majority of the shoes in American closets are made from non-compostable, unrecyclable plastic. Not only is it the perfect minimalist shoe, but it also has all the style and comfort you’d ever want in an everyday sneaker.

+ Allbirds

Images via Katherine Gallagher / Inhabitat

Editor’s Note: This product review is not sponsored by Allbirds. All opinions on the products and company are the author’s own.