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Food waste calculator

Throwing away food wastes everything that went into growing, moving and chilling it. This works out roughly how much CO₂ that adds up to over a year, using published emissions factors, and shows you which numbers are solid and which are rough.

About this much CO₂ a year

2,808 kg CO₂e

From 104 kg of beef & lamb a year, at 27 kg CO₂e per kg.

  • Like driving 11,232 km
  • Or 339,768 phone charges
  • A tree would need 127.6 years to absorb it

That is roughly 104% of what an average person throws away in a year, which studies put near 100 kg.

The emissions factors

Kilograms of CO₂e produced per kilogram of food, covering production. Beef is roughly seventy times vegetables, which is why what you waste matters more than how much.

Emissions factors by food category
Categorykg CO₂e per kgConfidence
Beef & Lambsteak, ground beef, lamb chops, beef roast27Well established
Cheesecheddar, mozzarella, parmesan, brie11Well established
Porkbacon, pork chops, ham, sausage7.6Well established
Poultrychicken, turkey, chicken breast, chicken thigh6.9Well established
Seafoodsalmon, shrimp, tuna, cod5.4Varies by product
Eggseggs, egg whites, egg carton4.7Well established
Milk & Yogurtmilk, yogurt, cream, butter3.2Well established
Packaged & Processedchips, cookies, crackers, cereal3Varies by product
Mixed / Unknown2.5Varies by product
Grains & Breadbread, rice, pasta, flour1.6Well established
Legumes & Nutsbeans, lentils, chickpeas, peanuts1.4Well established
Beveragesjuice, soda, coffee, tea1Rough estimate
Fruitsapples, bananas, oranges, berries0.5Well established
Vegetableslettuce, broccoli, carrots, onions0.4Well established

Where these numbers come from

Food production factors are from Poore & Nemecek (2018), the largest meta-analysis of food system emissions, covering roughly 38,000 farms. Disposal factors are from the US EPA’s WARM model, version 16. Everyday equivalents use the EPA’s greenhouse gas equivalencies.

What this does not claim: it is an estimate for a category, not a measurement of your specific food. Emissions vary by farm, season and distance travelled, which is why seafood and packaged goods are marked as less certain. It counts production only, so it understates the full footprint by leaving out your own shopping trips and refrigeration.

Measure it instead of estimating it

SeePantry tracks what you actually use versus what you throw away, and reports the money and CO₂ behind both, with a methodology page that spells out the arithmetic. It also tries to stop the waste happening in the first place.

Download on the App StoreGet it on Google Play

Free to start. No account needed to try it.

How SeePantry tracks food waste