Brew Ratios
Why 1:16 became the filter default, what changes as you move away from it, and why espresso and cold brew use completely different numbers.
A brew ratio is water mass divided by coffee mass. "1:16" means 16 g of water for every 1 g of coffee — 25 g of coffee to 400 g of water.
Always work in grams. Scoops and millilitres of grounds vary wildly with roast level and grind; a scale that reads to 0.1 g is the single highest-value piece of gear you can buy.
Filter coffee: 1:15 to 1:18
The SCA "Golden Cup" standard is 55 g of coffee per litre of water, or about 1:18. Most specialty cafés brew a touch tighter, 1:15 to 1:17, and almost every popular pour over recipe lands in that band.
Move the ratio and strength moves with it:
- Tighter (1:14, 1:15) — more body, more intensity, slightly lower extraction because each gram of coffee sees less fresh water.
- Wider (1:17, 1:18) — lighter, more transparent cup, slightly higher extraction because there is more solvent per gram.
The extraction shift is small; the strength shift is large. That is the main reason to think of ratio as your strength knob and grind as your extraction knob.
Espresso: 1:1.5 to 1:3
Espresso ratios describe beverage out : dry coffee in, not water in. A "1:2" shot is 18 g in, 36 g out.
| Style | Ratio | Character |
|---|---|---|
| Ristretto | 1:1 – 1:1.5 | syrupy, intense, lower extraction |
| Normale | 1:2 – 1:2.5 | the modern default; ~9 % TDS |
| Lungo | 1:3 – 1:4 | lighter body, higher extraction, less bitterness |
| Turbo / allongé | 1:3+ in ~15 s | coarse grind, low pressure, very clean |
Espresso can hit 18–22 % extraction at 1:2 only because pressure, fine grind and high temperature drive extraction fast. Push the ratio longer and you can pull 23–25 % from a light roast without harshness — the extra water dilutes the bitter compounds even as it extracts them.
Immersion: 1:12 to 1:17
French press and AeroPress grounds stay in contact with all the water for the whole brew, so the extraction is more even but the concentration gradient falls as the brew proceeds. Immersion brews usually taste best a touch tighter (1:13–1:15) than the same coffee as a pour over, and AeroPress users often brew a concentrate at 1:6 and dilute afterwards — called bypass brewing.
Cold brew: 1:4 to 1:8 concentrate
Cold water extracts slowly. Brewing 12–24 hours at 1:8 produces a concentrate around 2–3 % TDS that is diluted 1:1 before serving. Brewed "ready to drink" at 1:15 the cup is often thin and under-extracted; the concentrate-and-dilute approach gets more out of the coffee.
A quick reference
| Method | Typical ratio | Water for 20 g coffee |
|---|---|---|
| Pour over | 1:16 – 1:17 | 320–340 g |
| French press | 1:15 | 300 g |
| AeroPress | 1:12 – 1:14 | 240–280 g |
| Moka pot | 1:7 – 1:10 | 140–200 g |
| Espresso (out:in) | 1:2 | 40 g beverage |
| Cold brew concentrate | 1:8 | 160 g |
Use the calculator to see how ratio interacts with grind, temperature and time for any of these methods.