Here at Helpsy, we reimagine secondhand clothing in the name of the planet. The EPA estimates that in 2018 textiles made up 5.8% of municipal solid waste generated. As a society we treat our clothing as disposable, and the state of our trash proves it. We want to bring awareness to the overconsumption problem in the world and work together towards solutions.

In getting a clearer picture of the problem, it’s important to use data to measure the impact of the choices we make, especially when it comes to discarding, reusing and buying clothing. That’s why we created this impact calculator: to help you, our community, understand that shopping with intention and buying secondhand has an effect on the planet! 

Our impact calculator calculates the approximate CO2 emission reduction and water usage savings from buying an item secondhand instead of new at a traditional retail store. The calculator is based on a simple formula created after consulting with scientists, research journals, and our own data that has been collected over years of sorting clothes. In full transparency, we want to share our sources, assumptions, and our math. We hope you like numbers!

Our Upfront Disclaimer 

We share this with a big qualifier--this is a work in progress and we welcome all input and feedback. We want to be in dialogue with our customers and the scientific community to continue working to make this calculator the best it can be.

Our Sources and Collaborators. 

This calculator was built by Callie Rabinovitz, Strategic Partnerships Intern, under the supervision of Lauren B. Fay, Director of Strategic Partnerships. We have worked and consulted with scientists, academics, and our peers in the secondhand space as sources and verifiers of our conclusions. Collaborators include James Rogers, Director of Sustainability at The RealReal which has their own Sustainability Calculator which was consulted, and this material has been reviewed by Kelsea Schumacher and Amanda Forster at the National Institute of Standards. We are proud to work with partners across sectors to better understand the full scope of the fashion waste crisis. 

Our Assumptions

Through researching yearly global fiber production,we’ve determined that the average “new” clothing item (anything made after 2010 in industry terms) is made of: 

  • 64% polyester
  • 31% cotton
  • 5% MMCF (Man-made cellulosic fibers ie viscose)

We have estimated that 92% of our stock falls into that “new” garment category meaning that, for now, all of our calculations are based on new fabric composition. 

We know that producing a kilogram of each of those fabrics produces approximately the following CO2 emissions: 

We also know that producing a kilogram of each of those fabrics uses approximately the following amounts of water:

We recognize that the purchase of one secondhand item does not fully offset the purchase of one new item. This could be because some items, like socks or underwear, are not feasible for many to buy secondhand. While there are a few estimates out there about what secondhand shopping’s displacement is there is still research to be done. In this version of the calculator we assume that the purchase of one secondhand item offsets the purchase of one new item. 

Our Calculations

So if we take out our pencils, we find that producing 1 kilogram of new clothing has the following environmental impact:

CO2 emissions: (0.64 x 12.7) + (0.31 x 14.5)+ (0.05 x 14) = 13.323 kg

Water usage: (0.64 x 59.8) + (0.31 x 9,800) + (0.05 x 640)= 3,108.272 kg

Thus we have our coefficients for CO2 emissions avoided and water saved as a result of purchasing a garment secondhand. 

For fun, let’s try an example.What is the environmental impact of a 0.4 kg piece of clothing manufactured in 2018?

CO2 emissions = 0.4 * 13.323/ 1kg

Water usage = 0.4 * 3,108.272/ 1kg

The garment’s footprint is 5.3292 kg CO2, 1,243.309 kg of water used. Then we do additional calculations to showcase our impact in something more familiar, like pounds and gallons or even miles driven (404 grams of CO2 emitted per mile) and days of drinking water (an average of 3.2 liters per person per day). 

That one item represents over 13 miles driving and over 350 days of drinking water. This is big! 

Our impact calculations are based on the average weight of an item per its category, meaning for the purposes of this calculator all t-shirts are the same weight, all pants are the same weight, all dresses are the same weight, etc… Our data is always being updated as we, alongside the industry, learn more and gather more information from our sorting process.Helpsy pledges to update this calculator twice a year with new information and of course aim to get more and more nuanced in our approximations.

There are plenty of clothes in circulation. If we can decrease our total number of purchases, buy secondhand when we do need new items, and treat our clothing well, we can collectively make a BIG impact. We believe we, as a reseller, can use our platform as an engine for good. Big picture? You’re making a difference shopping with Helpsy! 

Do you have input on our impact calculator? Let us know below, we’d love to chat. Email us at