What a brew ratio is
A brew ratio is the weight of coffee compared to the weight of water. "1:16" means 1 g of coffee for every 16 g of water, so 20 g of coffee brews with 320 g of water. Water weighs 1 g per ml, so grams and millilitres are interchangeable here.
A lower second number means stronger coffee (1:14 is stronger than 1:17). The Specialty Coffee Association's long-standing brewing guideline is about 55 g of coffee per litre of water, roughly 1:18, which makes a good reference point for drip and pour-over.
Ratios for every method
| Method | Start at | Grind | Brew time |
|---|---|---|---|
| Pour-over (V60, Chemex) | 1:16 | Medium-fine | 2:30–4:00 |
| Drip machine | 1:17 | Medium | 4–6 min |
| French press | 1:15 | Coarse | 4 min |
| AeroPress | 1:13 | Fine to medium | 1:30–2:30 |
| Cold brew concentrate | 1:8 | Coarse | 12–18 hours |
| Espresso | 1:2 | Very fine | 25–30 sec |
These are starting points, not rules. Plug any of them into our coffee ratio calculator to get exact amounts for the cup size you want.
Grind, temperature and time
Grind size controls how fast water extracts flavour. Finer grinds extract faster, so short brews (espresso, AeroPress) use fine grinds and long immersion brews (French press, cold brew) use coarse ones.
Water temperature for hot coffee should be around 90–96 °C (195–205 °F), just off the boil. Too cool and the coffee tastes flat and sour.
Brew time works with grind: if you grind finer, the water drains more slowly in a pour-over, so time and grind move together.
Fixing sour, bitter or weak coffee
| Your cup tastes… | Likely cause | Try this |
|---|---|---|
| Sour, sharp, thin | Under-extracted | Grind finer, use hotter water or brew longer |
| Bitter, harsh, drying | Over-extracted | Grind coarser or shorten the brew |
| Weak, watery | Too little coffee | Lower the ratio (e.g. 1:17 → 1:15) |
| Heavy, muddy | Too much coffee or fines | Raise the ratio or use a finer filter |
Change one variable at a time and write it down. Two or three brews is usually enough to dial in a new bag of beans.
The two upgrades that matter most
A burr grinder for an even grind and a scale with a timer. See coffee scales →
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