What dialling in actually means
Espresso has three main variables: grind size, dose (how much coffee), and yield (how much liquid espresso). These interact with each other — changing one affects how the others behave. Dialling in is the process of finding the combination that produces a balanced, sweet, repeatable shot.
Most home baristas make the mistake of changing multiple variables at once. This makes it impossible to know which change helped. The rule: change one variable at a time, pull a shot, taste it, and evaluate before changing anything else.
The starting recipe
If you're starting from scratch with a new coffee, use this recipe as your baseline:
- Dose: 18 g (double shot basket)
- Yield: 36 g (2× your dose weight)
- Time: 25–30 seconds from pump start
- Water temperature: 93 °C (199 °F)
This 1:2 ratio (dose to yield) is a solid starting point for most medium-roast coffees. Light roasts often benefit from a slightly longer yield (1:2.2 to 1:2.5). Dark roasts often taste better with a shorter yield (1:1.8 to 1:2).
Which variable to change first: always grind
Grind size is your primary dial. Keep dose and yield constant and adjust grind until the shot takes 25–30 seconds. Don't touch dose or yield until grind is dialled in.
- Shot pulls in under 20 seconds: Grind finer
- Shot pulls in over 35 seconds: Grind coarser
- Shot pulls in 25–30 seconds but tastes sour: Grind finer (extract more)
- Shot pulls in 25–30 seconds but tastes bitter: Grind coarser (extract less)
Using taste to guide your adjustments
Sour or sharp: Under-extracted. Grind finer (increases extraction). If you're already hitting target time, try increasing your yield by a few grams.
Bitter or harsh: Over-extracted. Grind coarser (decreases extraction). If time is already correct, reduce your yield by a few grams or lower water temperature 1–2 degrees.
Weak or watery: Both under-extracted AND under-dosed. First grind finer, then if it's still thin, increase dose by 0.5 g.
Balanced but needs more body: Reduce yield slightly (shorter shot). This concentrates the flavour.
When to adjust dose
Only adjust dose after grind is dialled in. Dose affects body and strength more than flavour balance. If the shot is balanced but light-bodied, add 0.5 g. If it's balanced but too intense, reduce by 0.5 g. Dose adjustments in espresso are very small — changes of more than 1 g at a time will significantly alter the shot.
Keeping notes
Write down every shot: grind setting, dose, yield, time, and a taste note. Without notes you'll forget what worked and repeat the same mistakes. You only need two or three shots to dial in most coffees — with notes. Without notes, you can chase the same problem for weeks.