The French press is the cheapest way to make good coffee and the easiest way to make bad coffee. The difference is ratio, grind and one small habit nobody teaches.
The standard ratio
1:15 by weight. Twenty grams of coffee to 300 ml of water, which fills a small press. For a one litre press, use 66 g of coffee.
| Press size | Coffee (1:15) | For a stronger cup (1:13) |
|---|---|---|
| 350 ml | 23 g | 27 g |
| 600 ml | 40 g | 46 g |
| 800 ml | 53 g | 62 g |
| 1000 ml | 66 g | 77 g |
Grind and water temperature
Coarse grind, raw sugar texture. Because extraction is entirely by contact time rather than flow, French press is more forgiving of grind than pour-over, but fine particles are what make the cup muddy.
Water at 93 to 96 C for medium and light roasts, and 88 to 92 C for dark roasts. Off the boil for thirty seconds is close enough without a thermometer.
Why the crust matters
When you pour water, a crust of grounds floats on top. This crust is a filter bed, and letting it sit intact for four minutes gives you a cleaner cup. Break it with a spoon at four minutes, skim the foam and floating particles, then plunge.
The skimming step is what separates a clear cup from a cloudy one. It takes ten seconds and it is the single biggest difference between a decent French press and a great one.
The plunge
Slowly, over 15 to 20 seconds, and stop when you meet resistance. Never press hard to force it down. Pour immediately, and stop pouring with about 50 ml left, because that last measure is mostly sediment.
The recipe, in full
- Weigh 20 g of coarse coffee per 300 ml of water.
- Pour all the water at once, start your timer.
- At 4 minutes, break the crust with a spoon and skim the foam.
- Plunge slowly, stop at resistance.
- Pour immediately, leaving the last 50 ml behind.
Why 1:15 and not something else
Immersion needs a slightly stronger ratio than pour-over because the coffee sits in water that is steadily cooling and there is no flow to replenish fresh solvent against the grounds. At 1:17 an immersion cup often tastes thin; at 1:13 it becomes too heavy for gentle beans.