Tool
Milk drink builder
Pick a drink and a cup size and get the espresso, the milk to steam and the foam to aim for — plus a mode that works backwards from what you poured.
Milk to steam
181 ml
144 ml goes in the cup, of which roughly 50 ml is foam. Steam a little extra: milk expands and some always stays in the jug.
Foam: A deep, airy foam layer — traditionally about a third of the drink.
Jug: a 600 ml jug, filled to between a third and a half. Milk takes up more room once textured; how much depends on the foam.
The Italian convention is roughly equal thirds of espresso, milk and foam in a small cup. Much of the rest of the world serves it considerably larger.
How this was worked out
Milk in the cup = cup size − espresso
180 − 36 = 144 ml
Espresso is weighed and milk is measured by volume; the two are treated as interchangeable here, which is close enough for building a drink.
Milk to steam = milk in the cup + 15% + 15 ml
144 + margin = 181 ml
The margin covers what clings to the jug. The fixed part matters at small volumes, where a percentage alone is not enough to pour.
- To change the balance
- If the drink tastes too milky, use a smaller cup or a second shot. If the coffee is too forward, use a larger cup. Changing the cup changes the balance; steaming more or less milk for the same cup only changes how full it is.
- Keep the same
- The shot. Keep the espresso the same while you try a different cup size, so that any change in the balance comes from the milk.
- What this cannot tell you
- Only the subtraction is exact. The foam figure is the convention for this drink, not a measurement of your milk. The extra for the jug is a rule of thumb, and how much milk expands depends on the milk and on how long air is let in. Cafés also make the same named drink in different sizes, so treat the numbers as a starting point.
An evidence-based range, not a measurement
How it works
Each drink carries a conventional espresso base and a foam character. The milk to steam is the cup size minus the espresso, plus a little extra because milk never pours out of the jug completely and steamed milk expands. Working backwards, the amounts you enter are compared against those same conventions to find which drink they sit closest to.
What the inputs mean
- Cup size
- The capacity of the vessel, not the volume of drink. Fill to a few millimetres below the rim.
- Foam level
- How much of the milk is aerated. A cortado is barely textured; a cappuccino is roughly a third foam.
- Milk to steam
- How much cold milk to put in the jug. Slightly more than the drink needs, because milk expands and some stays behind.
Worked examples
A cappuccino in a 180 ml cup
- Cappuccino
- Cup 180 ml
- Double espresso
Result: About 36 g of espresso and roughly 145 ml of milk to steam, aiming for about a third foam.
A flat white in a 160 ml cup
- Flat white
- Cup 160 ml
- Double espresso
Result: About 36 g of espresso and roughly 125 ml of milk, aiming for a thin microfoam layer.
Common mistakes
Steaming exactly the amount the drink needs
Milk expands and some always stays in the jug. Steaming a little extra is normal; steaming far too much wastes it and makes texturing harder.
Filling the jug more than half full
Textured milk takes up more room than it did cold, by an amount that depends on how much air goes in. Above half, it is likely to go over the rim.
Treating the closest-drink answer as a definition
It reports which convention your amounts sit nearest to. A drink between two conventions is a perfectly good drink.
What the result does not mean
- These proportions are not a rule any café is obliged to follow, and a flat white in Australia is not the same drink as a flat white in London.
- Milk volume does not tell you whether the milk was textured well. That is the steaming technique.
What this does not account for
- Drink proportions are conventions, not standards. Cafés in different countries build the same drink very differently, and neither is wrong.
- Foam is treated as a proportion of the milk rather than measured separately, because nobody measures foam volume at home.
- Assumes a double espresso base unless you say otherwise.
Where to go next
Learn the technique
Background reading
Equipment involved
Drinks and methods
When it goes wrong
Practise this in a lesson
Become a Barista · Level 5
The café menu as a small set of decisions about espresso, water, milk and foam.
- At the machine: Write down what your drinks are
Become a Barista · Level 6
The task: Enter the two milk drinks you make most often, with the cups you actually own. Note how much cold milk each needs, add them, and mark that level on your jug with a strip of tape.