Shoe Company Allbirds Invests $2 Million in Plant-Based Leather

The new material has a carbon footprint 40x smaller than real leather.

Allbirds plant-based leather
The new plant-based leather is made from vegetable oil, natural rubber, and other bio-inputs.


Allbirds is a company that never stops innovating. After the smashing success of its all-wool running shoes, eucalyptus fiber sneakers, recycled plastic laces, castor bean oil insoles, and a new clothing line that includes odor-fighting fabric made from crab shells, you'd think it might rest on its laurels for a bit, raking in the accolades from delighted and loyal fans; but no, it's on to another, even more impressive project.

Plant-based leather is Allbirds' next big goal. The company recently announced a $2-million investment in a material innovation firm called Natural Fiber Welding, Inc. and says it will be adding "the world's first 100% natural plant-based leather" to its product lineup by December 2021. This material, which is called Mirum, is said to have 40 times less carbon impact than real leather and produce 17% less carbon than synthetic leather made from petroleum-based sources. MIRUM is made from a combination of vegetable oil, natural rubber, and other bio inputs. 

From NFW's website, "Mirum is made with natural, biodegradable polymers. Our finished materials are never coated in polyurethane and use no synthetic binders. Mirum stands for 100% natural inputs and zero use of plastic." The material uses a mix of virgin and recycled plant matter.

Allbirds plant-based leather ingredients
A view of ingredients used in NFW's plant leather.


The absence of polyurethane coatings stands out in an industry that often does put a layer of plastic over other plant-based leather alternatives as a way of sealing and protecting them. That Mirum can be constructed without it is impressive – and sets a high bar for the rest of the vegan leather industry. It also means that the material can biodegrade at the end of its life without leaving traces of plastic in the soil, or it can be reground into new Mirum for completely circular production.

When asked why Allbirds didn't pursue other pre-existing plant-based leather options, such as those made from pineapple, cork, or apple skins, Claudia Richardson, senior manager of materials innovation, explained that Mirum's technology "had the right combination of innovation, carbon reduction capability and scalability that we needed." She went on:

"Their technology can produce a 100% natural, plant-based alternative leather that doesn't rely on plastic. To pursue our mission to eliminate petroleum from the fashion industry, we find new processes and materials that can be easily replicated and repeated – and NFW’s solution is truly scalable. With Mirum™, we’re answering a century-long quest for a greener solution to leather that potentially has an over 95% reduction in carbon emissions. This could have a major impact in the fashion industry and beyond. We’re excited to bring Plant Leather to Allbirds’s suite of open-source natural materials, knowing this could help other brands, as well. 

Joey Zwillinger, co-founder and co-CEO of Allbirds, said in a press release, "For too long, fashion companies have relied on dirty synthetics and unsustainable leather, prioritizing speed and cost over the environment. Natural Fiber Welding is creating scalable, sustainable antidotes to leather, and doing so with the potential for a game-changing 98% reduction in carbon emissions. Our partnership with NFW and planned introduction of Plant Leather based on their technology is an exciting step on our journey to eradicate petroleum from the fashion industry."

If successful – and no doubt it will be – this could revolutionize the shoe industry, eliminating ethically questionable leather and plastic-based vegan leathers that pollute the environment at the end of their life cycle. Allbirds sees its investment as not only smart business strategy, but a contribution to the betterment of the planet. 

"There is urgent work to do, and it can’t be done alone," the press release states. "The business community must all be willing to invest in a greener future. As Allbirds drives towards a bigger goal of emitting zero carbon, they are proving that a sustainable future is possible, but only if all businesses are held accountable for their environmental impact."