Espresso Ratio Calculator

Dose, yield, ratio

Three numbers define an espresso recipe. The dose is the dry coffee in the basket, the yield is the liquid espresso in the cup, and the brew ratio is yield divided by dose. A modern standard shot is 18 g in, 36 g out — a 1:2 ratio — in somewhere around 25 to 32 seconds. Fix any two and the third follows, which is exactly what this calculator does.

Ristretto, normale, lungo

Ratios under about 1:1.5 are ristretto territory: intense, syrupy, muted acidity, and unforgiving of an uneven grind. 1:1.5 to 1:2.5 is the normale range where most cafes and most beans live. Push past 1:2.5 into lungo and you trade body for clarity and higher extraction — often a good call for lighter roasts that taste sour and underdeveloped at 1:2.

Dialling in

Keep the dose fixed to whatever your basket is designed for — changing it moves everything at once. Then use grind to control time and ratio to control style. Sour, sharp, fast shots want a finer grind; bitter, harsh, slow ones want coarser. If a shot is balanced but too intense, lengthen the ratio rather than grinding coarser. And always judge by taste, not by the clock: the timer is a diagnostic, not the goal. Logging each change — dose, yield, time, grind setting — is what turns twenty sink shots into five.

How it works

Choose which number to solve for and the calculator greys that field out and fills it in from the other two. Yield is dose × ratio, dose is yield ÷ ratio, and ratio is yield ÷ dose. Dose and yield are shown to a tenth of a gram, the ratio to two decimal places.

It then names the style from yield ÷ dose. Anything below 1:1.5 is a ristretto, 1:1.5 up to and including 1:2.5 is a normale, and anything longer than 1:2.5 is a lungo.

A worked example

You dose 18.5 g into the basket and stop the shot when the scale under the cup reads 42 g.

A comfortable normale, a little longer than the textbook 1:2. For this dose the lungo line sits at 18.5 × 2.5 = 46.25 g, so letting the shot run much past 46 g changes the label. To hit exactly 1:2 instead, solve for yield: 18.5 g in calls for 37 g out.