Coffee Brew Ratio Calculator
Pick your brewing method, set your coffee and water amounts, and get a step-by-step pour guide with a built-in timer. Covers V60, AeroPress, Chemex, French Press, Moka Pot, Cold Brew, and more. Save your favourite recipes.
Brew Strength
Learn more: brew ratios, TDS, and cup yield
Why each method gets its own ratio window
Brew ratio is grams of water per gram of coffee, and the calculator keeps a separate range for each of its ten methods. The three paper-filter drippers sit together at 14:1 to 18:1, with 16:1 preselected for V60, Chemex, and Kalita Wave.
Immersion brewers run slightly lower. French press allows 13:1 to 17:1, and both the Clever Dripper and the siphon allow 13:1 to 16:1, each starting at 15:1. AeroPress goes lower still at 10:1 to 15:1, since the short steep and the press give you a small concentrated serving rather than a full mug.
Three methods sit well below the rest: moka pot at 7:1 to 11:1, Vietnamese phin at 6:1 to 9:1, and cold brew at 6:1 to 10:1. In each case much less liquid reaches the cup than the water you poured in, or the result gets diluted before you drink it.
The TDS figure comes from your ratio, not a measurement
Total dissolved solids is the share of your drink that is dissolved coffee rather than water. The calculator assumes 20% of the coffee's mass dissolves, the midpoint of the 18 to 22% extraction window specialty coffee aims for, so the percentage it shows is 20 divided by your ratio.
At 16:1 that gives 1.25%, which the strength meter labels Balanced (SCA gold standard). The zones read Watery below 1.00%, Light up to 1.15%, Balanced up to 1.35%, Bold up to 1.55%, and Strong above that, so roughly 14.9:1 through 17.3:1 falls in the balanced band.
The low-ratio methods behave as you would expect. AeroPress at its default 12:1 estimates 1.67% and reads Strong. Cold brew at 8:1 estimates 2.50%, and the 1:1 dilution suggested in that method's note brings it back to about 1.25%.
Because extraction is fixed at 20% in that formula, the number moves only when your ratio moves. A refractometer on the same cup will read differently whenever your real extraction is off 20%, and that is what grind size and contact time control.
The 18 to 22% target is older than the equipment used to check it. Coffee Chronicler's history of the Golden Cup standard traces it to 1957 work at the Midwest Research Institute, which widened a 17.5 to 21.2% range published earlier by the National Coffee Association's brewing committee.
Bloom water and how much coffee reaches the cup
Three methods give you a bloom timer, and the calculator sizes that first pour from your dose: 2.5 times the coffee weight for V60, 3 times for Chemex, and 2 times for Kalita Wave. A 20 g V60 dose gets a 50 g bloom, and the rest of the water goes in three pours of 40%, 35%, and whatever remains. The Vietnamese phin schedule opens with a fixed bloom of 1.5 times the dose, without a timer of its own.
The yield stat subtracts the water the wet grounds hold onto. The calculator uses 2 g of water per gram of coffee for V60, AeroPress, Kalita, Clever, and phin, 2.5 for Chemex, 1.8 for French press, 1.5 for siphon, and 3 for cold brew.
So 20 g in a V60 at 16:1 uses 320 g of water and leaves about 280 g in the carafe. Cold brew gives up the most: 50 g of coffee at 8:1 starts with 400 g of water and yields around 250 g. The moka pot is treated separately, as a flat 62% of the water in the boiler, so 15 g at 8:1 turns 120 g of water into roughly 74 g of coffee.
FAQ
How much water should I use for the bloom?
Two to three times the weight of the coffee. This calculator uses 2.5 times for V60, which is 50 g for a 20 g dose, 3 times for Chemex, and 2 times for Kalita Wave. The bloom timer runs from 15 to 60 seconds and starts at 45.
Why does my coffee taste sour at the recommended ratio?
Sour means under-extraction, and the ratio is rarely the first thing to change. The dial-in advisor suggests grinding one or two steps finer first, then raising the water temperature by 2 to 3 °C, pouring more slowly to extend contact time, and only after that lowering the ratio.
What water temperature suits light, medium, and dark roasts?
The roast buttons suggest 94 to 96 °C for light, 91 to 93 °C for medium, and 87 to 90 °C for dark. They show a hint only and do not move the temperature slider for you. Moka pot and cold brew show no hint at all, since neither is brewed at a kettle temperature you set.