Espresso Basics: Dose, Yield and Time

Dose: coffee in

Dose is the mass of dry ground coffee placed in the basket. Weigh it after grinding rather than trusting a grinder timer or measuring spoon.

The basket determines the sensible dose range. If it is designed for about 18 g, begin near 18 g. A 14 g basket and a 22 g basket need different doses because the coffee bed must sit at a workable depth with enough space above it for the machine’s shower screen.

Too little coffee can leave a shallow, wet puck and produce very fast flow. Too much can press the puck against the shower screen, disturb the surface and restrict flow. More coffee does not automatically mean stronger or better espresso; it means you have changed the recipe.

Choose a dose that suits the basket, then keep it fixed while dialing in. A variation of half a gram can be enough to change shot time.

Yield: espresso out

Yield is the mass of espresso in the cup. Measure it in grams, not millilitres. Crema contains gas and can make two visually identical cups contain different amounts of liquid.

Yield determines the brew ratio:

Dose	Yield	Brew ratio	General character
18 g	27 g	1:1.5	Shorter, heavier and more concentrated
18 g	36 g	1:2	Balanced starting point for many coffees
18 g	45 g	1:2.5	Longer, lighter and often more extracted

To calculate the ratio, divide yield by dose. A 36 g yield from an 18 g dose is 36 ÷ 18 = 2, or 1:2.

Longer is not always better. Increasing yield usually extracts more from the coffee, but it also makes the drink less concentrated. Darker roasts may taste balanced with a shorter ratio, while lighter roasts may benefit from a little more yield.

Time: a diagnostic clue

Time tells you how quickly water moved through the coffee bed. It helps reveal whether the grind and puck preparation created sensible resistance.

Choose one timing convention and use it consistently. On most home machines, the simplest method is to start the timer when you start the pump and stop it when the target yield is reached. Machines with long or adjustable pre-infusion make direct time comparisons less useful, so compare shots made with the same machine settings.

For an 18 g in, 36 g out starting recipe, roughly 25–35 seconds is a practical first target. Then taste:

• 36 g in 18 seconds will often be thin, sharp or underdeveloped;
• 36 g in 50 seconds may be dry, harsh or overly heavy;
• 36 g in 30 seconds can still taste poor if the coffee, temperature or puck preparation is wrong.

The clock is evidence. Your palate delivers the verdict.

Why all three numbers matter

“My espresso took 30 seconds” is not a complete recipe. Thirty seconds could produce 20 g or 70 g of liquid, and those drinks will taste very different.

Record the recipe in this order:

18 g dose → 36 g yield → 29 seconds

Add the grinder setting and a short taste note if you want to repeat or improve it:

Grinder 8 · sweet, slight sharp finish

This gives you a useful comparison for the next shot.

What to keep fixed

During the first stage of dialing in:

1. Use the same coffee.
2. Keep the dose fixed.
3. Stop at the same yield.
4. Keep water temperature and pre-infusion unchanged.
5. Adjust grind size to change the shot time and flow.

Once the shot lands in a sensible range, taste it. Only then decide whether the ratio itself needs changing.