Coffee Ratio Calculator
How much coffee or tea to use for an amount of water at your brew ratio, how many cups a bag of beans makes, and the extraction yield from a TDS reading.
Result…
How it's calculated
Coffee = water ÷ N · Water = coffee × N (for a ratio of 1:N by weight) Cups from beans = beans ÷ (water per cup ÷ N) Extraction yield (%) = TDS (%) × drink weight ÷ coffee dose 1 US fl oz = 29.5735295625 mL; 1 oz = 28.349523125 g; 1 mL of water ≈ 1 g
A brew ratio of 1:N means N grams of water for every gram of coffee or tea, by weight. Divide the water by N to get the coffee, or multiply the coffee by N to get the water; a bag of beans then makes as many cups as it holds doses. Water is weighed, and 1 mL of water weighs about 1 g, so millilitres work too. US fluid ounces of water and ounces of coffee are converted to grams with the exact factors. Extraction yield is a different measure: it uses a refractometer's TDS reading, the percentage of the drink that is dissolved coffee, times the drink's weight to find how many grams dissolved, then divides by the dose. No ratio or yield is the right one for everyone.
Your numbers, step by step
About the Coffee Ratio calculator
This coffee ratio calculator turns a brew ratio into amounts. Enter your ratio as 1 part coffee or tea to N parts water by weight, then the water you plan to use to get the coffee, or the coffee you have to get the water, along with how many cups that makes. A second mode counts how many cups a bag of beans or loose-leaf tea will brew at your ratio and cup size. A third works out extraction yield from a refractometer: the TDS reading times the drink's weight, divided by the dose. Grams and millilitres or ounces and US fluid ounces both work, using exact conversion factors. It suits home brewers, baristas dialling in a recipe, and anyone making coffee for a crowd. The working is shown, and no ratio is presented as the only right one.
How to use it
- Choose what “I want”: coffee and water, cups from beans, or extraction yield.
- Pick the “Units” and enter the “Brew ratio, 1 part coffee to” from your recipe.
- For coffee and water, choose what “I know the” and enter the “Water” or “Coffee or tea”, then the “Water per cup”.
- For cups from beans, enter the “Beans or leaves you have” and the “Water per cup”.
- For extraction yield, enter the “TDS (total dissolved solids)”, the “Drink weight” and the “Ground coffee used”.
Worked example
For 750 mL of water at 1:15, use 750 ÷ 15 = 50 g of coffee, which makes 3 cups of 250 mL at 16.67 g each. A 340 g bag at 1:16 with 300 mL cups needs 300 ÷ 16 = 18.75 g per cup, so it makes 340 ÷ 18.75 = 18.1 cups. A 320 g drink brewed from 20 g of coffee that reads 1.35% TDS holds 4.32 g of dissolved coffee, an extraction yield of 4.32 ÷ 20 = 21.6%.
Updated
Questions people ask
How do I work out how much coffee to use for my water?
Divide the water in grams by the N in your 1:N ratio. Since 1 mL of water weighs about 1 g, 600 mL at 1:16 needs 600 ÷ 16 = 37.5 g of coffee. Without scales, the cups to grams converter helps, and the ratio calculator scales any ratio.
What is the formula for coffee extraction yield?
Extraction yield (%) = TDS (%) × drink weight ÷ dry coffee dose. It is the share of the ground coffee's weight that dissolved into the drink.
What is the difference between brew ratio and TDS?
The brew ratio is the coffee and water you start with. TDS is how concentrated the finished drink is. Two brews at the same ratio can have different TDS if one extracts more from the grounds.
Why use the drink's weight and not the water I poured?
The wet grounds hold back some water, so less liquid ends up in the cup than went in. Using the water poured overstates the extraction yield, which is a common mistake.
Does the coffee ratio calculator work for tea and espresso?
Yes, as long as you enter the ratio your method uses: tea, espresso and cold brew all use very different ratios from filter coffee. It cannot judge taste, so treat the numbers as a starting point and adjust to your beans or leaves.