95
Estimated land-animal equivalents
Mostly chickens — the species killed in the largest numbers.
Veg.ac · Impact calculator
What does your plate
Pick your current diet and how long you'd commit to plant-based eating. The estimates below come from peer-reviewed lifecycle and food-system studies.
Your current diet
Time horizon
1 yr1102550
200
Estimated aquatic-animal equivalents
Fish, shrimp, and bycatch you would otherwise have eaten or financed.
1.9k kg
CO₂-equivalent avoided
≈ 804 litres of petrol burned.
750k L
Water saved
≈ 5k days of household water use.
2.4k m²
Estimated land demand reduced
≈ 0.48 football pitches.
130 m²
Estimated forest-pressure reduction
From land-use change driven by beef and feed soy.
360 kg
Estimated feed demand reduced
Globally, ~77% of soy and ~36% of cereal grains feed livestock.
—
And your daily life
Well-planned plant-based diets may improve LDL cholesterol and other cardiometabolic risk factors; individual outcomes vary.
More calculators
Different ways to see the same truth: small daily choices add up to enormous lifetime totals.
Per-meal swap
Swapping one beef-based meal for a bean-based one saves, on average:
- ~50 kgCO₂e avoided
- ~15,000 Lwater saved
- ~64 m²land freed
Per-kg figures: Poore & Nemecek (2018), Science.
Since I went vegan
Pick a date and we'll show the running totals you've already saved.
Family / classroom / office
Multiply one omnivore year by your group size to see what a single year of collective change looks like.
Animals1.9k
CO₂e37k kg
Water15.0M L
Make the numbers real. Start the 7-day plan.
One new plant-based habit a day, built on the ingredients you already cook.
Sources & methodology
Per-omnivore-year baselines combine Poore & Nemecek (Science, 2018), FAO statistics, faunalytics estimates of animals killed per capita, and the Water Footprint Network. Diet multipliers approximate dietary impact relative to an average omnivore in a high-income country.
Numbers are illustrative modeled estimates, not guaranteed savings. Land and feed reductions do not automatically restore forests or transfer grain to people.
Key takeaways
- Eating plant-based reduces demand for farmed animals and can substantially cut food emissions; estimated savings depend on your starting diet.
- Plant-based eating can reduce your food-related water footprint; the savings depend on the foods and where they are produced.
- Plant-based diets generally need less agricultural land — creating opportunities for ecosystem restoration if land use changes.
- The math is not marginal: changing your diet can substantially reduce the climate impact of your food.
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Frequently asked questions
Poore & Nemecek (Science, 2018) provide environmental-impact data; USDA and FAO provide slaughter statistics. Calculator results are estimates that depend on assumptions about diets, production and demand.
Method
How the impact calculator estimates your footprint
The calculator scales fixed annual baseline estimates by your diet setting and time period. It illustrates possible differences rather than calculating a personalised life-cycle assessment; the assumptions matter as much as the displayed total.
What a life-cycle assessment covers
Food life-cycle studies can include land-use change, farming, feed, processing, transport, packaging and retail. This calculator does not model those stages individually: it scales fixed annual estimates using a diet multiplier. Its outputs should be treated as illustrations, not measured savings.
Why methane and land use dominate
Ruminant digestion produces methane, a gas with roughly 80 times the warming effect of CO₂ over twenty years, and pasture expansion converts forest and savannah into grazing land, releasing stored carbon. Together these two mechanisms explain why beef and lamb sit an order of magnitude above legumes on almost every metric, and why 'local' rarely rescues them — transport accounts for under 10% of most products' emissions.
The parts that are genuinely uncertain
Soil carbon storage under improved grazing is context-dependent, time-limited and reversible; it does not generally cancel livestock emissions. Aquaculture varies by species and feed. Standard footprints also often omit the carbon that recovering vegetation could store if farmland were released.
Reading your result
Treat the output as an illustration rather than an audit. Both the total and the comparison depend on fixed baseline assumptions and diet multipliers. A displayed reduction is a result of this model, not a guarantee that the same percentage applies to your own diet.
Footprint per kilogram of food produced
Indicative food footprints per kg: kg CO₂-equivalent, m²-years of land use and litres of freshwater.
| Food | kg CO₂e / kg | Land m² / kg | Water L / kg |
|---|---|---|---|
| Beef (beef herd) | 99 | 326 | 15,400 |
| Lamb & mutton | 40 | 370 | 10,400 |
| Cheese | 24 | 88 | 5,600 |
| Pork | 12 | 17 | 6,000 |
| Poultry | 10 | 12 | 4,300 |
| Eggs | 4.7 | 6 | 3,300 |
| Tofu | 3.2 | 2 | 2,500 |
| Beans & lentils | 0.9 | 3 | 4,000 |
| Oat milk (per L) | 0.9 | 0.8 | 48 |
Poore & Nemecek (2018), Science; Water Footprint Network.
Getting an accurate estimate
- 1
Log a typical week, not a good one
Aspirational input produces flattering output. Use a week that includes the takeaway and the rushed dinner.
- 2
Count dairy properly
Cheese is the most commonly under-reported item in food footprints because it appears as an ingredient rather than a meal. Milk in coffee adds up too — five flat whites is roughly a litre.
- 3
Model one change at a time
Run your baseline, then change a single category. The isolated deltas tell you where effort pays; the combined total tells you very little about priority.
- 4
Re-run after three months
Habits drift in both directions. A quarterly re-run catches regression early and is far more informative than a single snapshot.
Where effort actually pays
High-leverage changes
- Replacing beef and lamb, even partially — the single largest lever in almost every diet.
- Cutting cheese, which is the highest-impact food most people never think about.
- Switching dairy milk to a plant milk: generally lower emissions, land use and freshwater use.
- Reducing food waste, which accounts for around 6% of global emissions on its own.
Low-leverage distractions
- Optimising for food miles while keeping the same animal products.
- Assuming organic means lower emissions — yields are lower, so land use is often higher.
- Avoiding avocados and almonds while eating beef weekly.
- Waiting for a perfect diet before making the first substitution.
Calculator questions
Is grass-fed beef better?
For animal welfare and local biodiversity it can be. For climate it is usually worse per kilogram, because grass-fed cattle grow more slowly and emit methane for longer, and because pasture requires far more land. Soil carbon offsets part but not all of that difference.
Are plant milks really lower impact than dairy?
Generally, yes. Compared per litre, plant milks usually have lower emissions, land use and freshwater use than dairy. The size of the reduction depends on the crop and indicator; almond milk uses more freshwater than soy or oat milk.
How much does transport matter?
Less than almost anyone expects. Transport is about 6% of global food emissions; for beef it is under 1% of the product's footprint. What you eat matters far more than how far it travelled.
Does the calculator include my whole carbon footprint?
No — food only. Heating, flights and driving are separate and often larger. Food is typically a quarter to a third of a household footprint in high-income countries.
Why do numbers differ from other calculators?
Different datasets, different system boundaries and different treatment of land-use change. Comparisons within one calculator are reliable; absolute figures across calculators are not.
Sources
- Poore, J. & Nemecek, T. (2018). Science, 360(6392), 987–992.
- IPCC (2019). Special Report on Climate Change and Land.
- Xu et al. (2021). Global greenhouse gas emissions from animal-based foods. Nature Food.
- Hayek et al. (2021). The carbon opportunity cost of animal-sourced food production.