Growing and processing the beans, and especially the milk, account for most of coffee’s footprint: dairy milk produces about 3.2 kg CO₂e and uses about 630 L of water per litre, while oat drink produces under 1 kg and uses about 48 L. Figures are averages; real values depend on the farm and supply chain.
How to use the Coffee Footprint Calculator
- Usual drink
- Number of drinks
- Per
- Milk
- Cup
- Sustainably grown coffee?
Results update as you type, and every field accepts the units shown in its menu.
How it works
Choose your usual drink, how many you have per day, week or month, the milk you use, your cup and whether the coffee is sustainably grown.
Tips
- Weigh coffee beans rather than using scoops – roast level and grind change how much a scoop holds.
- Grind just before brewing and match the grind size to the method (fine for espresso, coarse for French press and cold brew).
- Use filtered water just off the boil (90–96 °C / 195–205 °F) for hot coffee.
- Adjust the ratio to taste in small steps – one change at a time.
Common mistakes to avoid
- Using boiling water on green or white tea, which turns it bitter.
- Forgetting that caffeine content varies widely between drinks and brands.
- Comparing ratios written different ways (1:16 coffee:water vs 60 g per litre).
Inputs explained
| Field | What to enter |
|---|---|
| Usual drink | Choose one: Espresso, Double espresso / Americano, Filter / drip coffee, French press … |
| Number of drinks | A number |
| Per | Choose one: Day, Week, Month |
| Milk | Choose one: Dairy milk, Oat drink, Soy drink, Almond drink … |
| Cup | Choose one: Disposable cup, Reusable cup or mug |
| Sustainably grown coffee? | Choose one: No, Yes |
What each result means
- Cups per year = [Number of drinks]×[Per]
- Trees needed to absorb it = [Carbon footprint per year]÷21
- Same CO₂ as driving an average car = [Carbon footprint per year]÷0.17
- Same CO₂ as charging a smartphone = [Carbon footprint per year]÷0.00822
- Footprint with oat drink, reusable cup and sustainable beans = [Cups per year]×([Coffee per cup]×0.003 + [Milk per cup]÷1000×0.9)
Example values
How the main result changes when Number of drinks changes and everything else stays at the example values above:
| Number of drinks | Carbon footprint per year (kg CO₂e) |
|---|---|
| 1 | 73 |
| 1.5 | 109.5 |
| 2 | 146 |
| 2.5 | 182.5 |
| 3 | 219 |
| 4 | 292 |
Formula
CO₂e per cup = coffee (g) × 10 g CO₂e/g (× 0.3 if sustainably grown) + milk (L) × milk factor + 0.05 kg for a disposable cup
Water per cup = coffee (g) × 20 L/g + milk (L) × milk water factor
Trees = yearly CO₂e ÷ 21 kg (one tree's yearly uptake)
Worked example
Inputs — Usual drink: Filter / drip coffee; Number of drinks: 2; Per: Day; Milk: Dairy milk; Cup: Disposable cup; Sustainably grown coffee?: No.
Results — Cups per year = 730; Carbon footprint per year = 146 kg CO₂e; Water footprint per year = 219,000 L; Caffeine per day (average) = 190 mg; Trees needed to absorb it = 7; Same CO₂ as driving an average car = 859 km; Same CO₂ as charging a smartphone = 17,762 times; Footprint with oat drink, reusable cup and sustainable beans = 32.9 kg CO₂e.
Frequently asked questions
What is the carbon footprint of a cup of coffee?
Roughly 0.1–0.2 kg CO₂e for black coffee and 0.4–0.8 kg for a large latte with dairy milk.
How much water does a cup of coffee take?
About 140 litres to grow and process the 7 g of beans in a small cup – more for larger cups.
How can I make my coffee greener?
Use plant milk, a reusable cup, sustainably grown beans and brew only what you drink.