Most of us are guessing at the bin

Most of what we could recycle at home never makes it into a recycling bin.^[2] Half of what Americans throw away ends up in a landfill,^[1] where rotting food gives off methane, a potent greenhouse gas.^[5]

• 1 in 5recyclables from U.S. homes actually gets recycled^[2]
• 1 in 6pounds of what goes in recycling bins doesn't belong there^[3]
• 24%of what goes to U.S. landfills is food, more than any other material^[1]
• 14.4%of U.S. human-caused methane came from landfills in 2022, the third-biggest source^[5]

Each bin follows local rules that change from city to city and item to item. Pick a finding to see it as people.

Six items people often get wrong, four choices. The answers follow the City of Cambridge rules the voice guide uses in our demo.^[11] Your city's rules may differ.

• Attention alone can backfire.Pictures of watching eyes above campus bins increased sorting errors in mixed recycling by 4.5 percentage points. Paired with the sorting instructions, the same nudge cut errors by 7 points.^[8]
• Item-by-item feedback teaches.People who got immediate feedback on each item in a sorting game sorted more accurately afterwards, even a week later. In residences where people played it, contamination fell and more food went to compost.^[9]
• A generic reminder isn't enough.A motion-activated “Please recycle right” message, played at 24 bin locations for 30 days, produced an estimated 5-point drop in contamination that was not statistically significant.^[10]

In these studies, prompts that only asked for attention did little or made things worse. What helped was information about where things go, and feedback on each item at the moment of sorting.