How We Calculate Blu-nit Scores
What a Blu-nit Actually Measures
A blu-nit tells you how many average-sized adult trees it would take to offset a product's environmental footprint in a single day. That's it — one number.
Here's how it works: we add up all the known greenhouse gas emissions involved in creating, shipping, and storing a product up to the point where you buy it. That includes carbon dioxide, methane, nitrous oxide, and fluorinated gases — all converted into their carbon equivalents using their Global Warming Potential. Then we divide that total by the amount of carbon one average adult tree can absorb (sequester) in one day.
The result is your blu-nit score. A product with a blu-nit score of 8 means it would take 8 trees working for a full day to offset the emissions that went into getting that product to you. The higher the number, the heavier the environmental footprint.
We designed it this way on purpose. You don't need a degree in environmental science to understand a blu-nit, just like you don't need a degree in nutrition to understand a calorie.
Where Our Data Comes From
We don't make numbers up. Every blu-nit calculation is built on published, peer-reviewed, or government-sourced emissions data. Our current sources include:
University of Michigan Center for Sustainable Systems — Carbon footprint factsheets for poultry, beef, and other protein sources
U.S. Environmental Protection Agency (EPA) — Greenhouse gas equivalency data, grocery store emissions benchmarks, and fluorinated gas profiles
USDA and Department of Energy data — Food production energy breakdowns across agriculture, transportation, processing, and handling
Published lifecycle assessments — Peer-reviewed studies on dairy, eggs, plant-based alternatives, and other food categories
Energy Star commercial building data — Emissions benchmarks for grocery store and food retail operations
For the full breakdown of every data point, assumption, and source we use, visit our Where Our Numbers Come From page.
As we build direct partnerships with producers, distributors, and retailers, we'll be able to replace estimated averages with real-world data from the actual supply chain — making every score more precise over time.
Why Your Location Matters
A carton of eggs in Portland, Oregon doesn't have the same environmental footprint as a carton of eggs in Miami, Florida. The farms are in different places, the trucks travel different distances, and the local energy grids run on different fuel mixes.
That's why we calculate blu-nit values by region. Transportation distances are measured from the known (or averaged) production and processing locations to the specific city where the product is sold. Right now, we offer region-specific blu-nit values for:
We're expanding to more regions as we grow. If your city isn't listed yet, reach out — we'd love to add it.
The Formula
Every blu-nit score follows the same core calculation. First, we determine the product's total carbon footprint across four stages of its journey:
Carbon_Total = C_Agriculture + C_Transportation + C_Processing + C_Handling
C_Agriculture — The emissions from growing, raising, or cultivating the raw ingredients (fertilizers, feed, fuel for farm equipment, methane from livestock, etc.)
C_Transportation — The emissions from shipping the product from its origin to its point of sale, based on distance, vehicle type, fuel efficiency, and cargo weight
C_Processing — The emissions from transforming raw ingredients into a finished product (for example, turning raw corn into cereal)
C_Handling — The emissions from storing and refrigerating the product at the retail level, calculated based on the store's energy footprint and the product's estimated shelf life
Then we convert that total into blu-nits:
Blu-nit Score = Carbon_Total ÷ Carbon Sequestered by 1 Tree per Day
We intentionally measure from "cradle to point of sale" rather than the full "cradle to grave" lifecycle. Why? Because the full lifecycle — which includes what you do with the product after you buy it (how you cook it, whether you waste it, how you dispose of the packaging) — varies wildly from person to person and is nearly impossible to standardize. Our goal is to simplify, not overwhelm. By stopping at the point of sale, we give you a clean, comparable number that reflects what the industry is responsible for — the part of the footprint that producers, transporters, and retailers can actually control and improve.
What We Don't Measure (Yet)
We believe honesty builds trust, so here's what our model doesn't currently capture:
Water usage — Agricultural water consumption varies dramatically by crop and region but is not yet factored into the blu-nit score
Biodiversity impact — Land use changes, habitat disruption, and effects on ecosystems are real but difficult to express as a single number
Post-purchase emissions — Cooking, food waste, and packaging disposal are excluded (as explained above)
Social and labor impacts — Working conditions, fair trade considerations, and community effects are outside our current scope
We plan to expand the model over time. Water usage and land use are our next priorities. But we'd rather give you an accurate score on what we can measure well today than a vague score that tries to capture everything at once.
Have questions about our methodology? We welcome them. Contact us — we're happy to walk you through the math.
Want blu-nit scores calculated for your menu or product line? See what we offer businesses.