Coffee Ratio Calculator
Weak and under-extracted need opposite fixes.
Work out Coffee Ratio. Weak and under-extracted need opposite fixes. Names the misconception directly.
Coffee
29.9 g
Filter / pour over at 1:16.7 · 500 g of water
Grounds retain roughly two grams of water per gram of coffee, which is why a 500 g brew yields around 440 ml in the cup. Recipes that quote a cup volume rather than a water weight are quietly ignoring that. Extraction yield and strength are different things. Yield is what percentage of the coffee dissolved — 18 to 22% is the balanced band. Strength is how concentrated the result is, and the ratio sets that independently. This means a weak brew and an under-extracted one need opposite fixes. Weak wants more coffee; sour and under-extracted wants a finer grind or a longer contact time. Adding more coffee to a sour brew makes it stronger and still sour.
How the Coffee Ratio Calculator works
Coffee and water for filter, French press, AeroPress, espresso, moka and cold brew, with brewed volume after the grounds take their share, plus strength and extraction assessed separately.
Also known as: coffee to water ratio for filter · how many grams of coffee for 500ml · why is my coffee sour · brew ratio for french press
Not medical advice. This calculator gives a general estimate, not medical advice. It cannot account for your individual health, medical history, or medication. Talk to a qualified healthcare professional before acting on any result.
Frequently asked questions
What is a good coffee to water ratio?
About 1:16 to 1:17 for filter, 1:15 for French press, 1:2 for espresso. These are starting points — the ratio sets strength, and preference varies widely.
Why is the brewed volume less than the water?
The grounds retain roughly two grams of water per gram of coffee. A 500 g brew yields around 440 ml in the cup, which recipes quoting cup volumes quietly ignore.
What is the difference between strength and extraction?
Extraction is what percentage of the coffee dissolved — 18 to 22% is balanced. Strength is how concentrated the result is, set by the ratio. They move independently.
My coffee is sour. Should I use more coffee?
No. Sour means under-extracted, so grind finer or brew longer. More coffee makes it stronger and still sour — the commonest wrong fix in home brewing.
What is TDS?
Total dissolved solids, the percentage of the brewed liquid that is coffee rather than water. The Specialty Coffee Association's ideal band is 1.15 to 1.35% for filter.
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