Food Carbon Footprint Calculator
Calculate the CO2 emissions from your weekly diet.
Compare beef, chicken, fish, vegetables, and dairy.
The food you eat is responsible for roughly 25–30% of global greenhouse gas emissions. Every food item has an associated carbon footprint — the total CO2 and equivalent gases produced during farming, processing, transport, and retail.
How the Calculation Works For each food type, you enter the number of portions you eat per week. Each portion has a known CO2 equivalent (CO2e) in kilograms. The calculator multiplies portions by their per-portion emission factor and sums the total.
Emission Factors Per Portion Portion sizes are standardized at roughly 100g of meat/fish, one egg, or one 250ml glass of milk:
- Beef (100g): 2.7 kg CO2e — the highest of any common food. Beef production involves methane from cattle digestion, land use change (often deforestation), and fertilizer for feed crops.
- Lamb/Mutton (100g): 2.4 kg CO2e — similarly high due to ruminant methane emissions and extensive land use.
- Pork (100g): 0.7 kg CO2e — considerably lower than red meat, though still significant.
- Chicken (100g): 0.43 kg CO2e — the most efficient common meat, with no ruminant methane.
- Farmed Fish (100g): 0.52 kg CO2e — varies widely by species and farming method. Salmon is higher; shellfish is much lower.
- Eggs (per egg): 0.20 kg CO2e — relatively low-carbon animal protein.
- Dairy/milk (250ml glass): 0.32 kg CO2e — driven largely by methane from dairy cows.
Understanding Your Annual Footprint Multiply your weekly total by 52 to get the annual food footprint. Benchmarks:
- US average annual food footprint: ~2,000 kg CO2e/year
- Vegan diet: ~600 kg CO2e/year
- Vegetarian diet: ~900–1,200 kg CO2e/year
- Omnivore (average): ~1,500–2,000 kg CO2e/year
- High meat diet: ~2,500–3,300 kg CO2e/year
Biggest Lever: Red Meat Swapping one beef meal per week for chicken reduces your annual food footprint by roughly 115 kg CO2e. Swapping for lentils reduces it by about 138 kg CO2e. These are among the largest single dietary changes a person can make.
Worked Example 3 beef portions + 2 chicken + 1 pork + 7 glasses of milk per week:
- Beef: 3 × 2.7 = 8.1 kg
- Chicken: 2 × 0.43 = 0.86 kg
- Pork: 1 × 0.7 = 0.7 kg
- Dairy: 7 × 0.32 = 2.24 kg
- Weekly total: 11.9 kg CO2e → Annual: ~619 kg CO2e from those foods alone