Why there is no single correct coffee ratio
The Specialty Coffee Association (SCA) recommends 60 grams of coffee per litre of water as a starting point for filter brewing -- roughly 6 g per 100 ml cup. But this standard applies to filtered drip coffee only. Espresso uses 7 to 9 g of coffee for 25 to 40 ml of water, a ratio of 1:3 to 1:4 -- around ten times more concentrated than filter coffee by volume.
In the UK, filter coffee has seen a strong revival through specialty coffee culture, but many households still use pod machines or instant coffee. For those switching to ground coffee, the biggest mistake is using too little: the 60 g/litre figure feels counterintuitive if you are used to a teaspoon per cup.
Find your ideal ratio with the coffee ratio calculator.
Pour-over, French press, AeroPress: how the method changes the ratio
| Method | Coffee per litre | Notes |
|---|---|---|
| Filter / drip | 55 to 65 g | SCA standard |
| French press | 70 to 80 g | Coarser grind, longer contact |
| Pour-over (V60) | 60 to 70 g | 3-minute brew, medium-fine grind |
| AeroPress | 11 to 18 g per 200 ml | Very flexible, depends on style |
| Espresso | 1:2 to 1:3 ratio | 7 to 9 g for 18 to 30 ml |
| Cold brew | 100 to 150 g per litre | 12 to 24 hour steep |
What the ratio alone does not control
Water temperature (88 to 96 degrees C depending on method), grind size, water hardness, and coffee freshness all affect the result as much as the ratio. If your coffee is bitter, try a shorter brew time or slightly coarser grind before adjusting the dose. If it tastes weak or acidic, increase the ratio or grind finer before adding more coffee.