What does “dialling in” actually mean?
Dialling in is the process of adjusting your espresso variables - grind size, dose, yield, and shot time - until your shot tastes the way it should. It’s something you do every time you open a new bag of coffee, because every coffee extracts differently.
Think of it like tuning a radio: you’re turning the dial until you find the signal. The good news is there’s a logical order to adjusting things, so you’re not guessing randomly.
The four variables - and what they do
Before you touch anything, understand what you’re working with:
Grind Size
Controls how fast water flows through the puck. Finer = slower flow, more extraction. Coarser = faster flow, less extraction. This is your primary dial.
Dose
The weight of dry coffee grounds going into the portafilter basket. Usually 16 - 18g for a double shot. Changing dose changes extraction significantly.
Yield
The weight of liquid espresso in the cup. Together with dose, this gives you your brew ratio (e.g. 1:2 means 18g in → 36g out).
Shot Time
How long the shot takes to pull, measured from when you start the pump. Target is usually 25 - 35 seconds for a standard espresso.
Step 1: Start with a recipe
Before pulling your first shot, lock in a starting recipe. A reliable default for a double espresso:
| Variable | Starting Point |
|---|---|
| Dose | 18g |
| Yield | 36g (1:2 ratio) |
| Shot time | 27 - 30 seconds |
| Water temp | 92 - 94°C |
Keep your dose and yield fixed while you dial in. The only variable you should adjust first is grind size. Changing two things at once means you won’t know what caused the change.
Step 2: Adjust grind size to hit your time
Pull your first shot. Weigh the output and time it. Then use this simple decision tree:
Grind finer. Water is rushing through too quickly - the puck isn't offering enough resistance.
Grind coarser. The puck is too tight and water can't flow properly - you'll get bitter, over-extracted flavours.
You're in the zone. Now taste it and decide if you need to fine-tune further.
Make small adjustments - one or two clicks on your grinder at a time. Run a purge shot after each adjustment (grind and discard a small amount) so stale grounds from the previous setting don’t carry over.
Step 3: Taste and adjust
Once your shot is in the right time window, tasting tells you whether to push further. Here’s how to interpret what’s in the cup:
“Sour, thin, sharp”
Under-extracted - not enough dissolved from the coffee.
Fix: Grind slightly finer, or increase your dose by 0.5g.
“Bitter, dry, harsh”
Over-extracted - too much dissolved, including the unpleasant compounds.
Fix: Grind slightly coarser, or reduce your yield (stop the shot a few grams earlier).
“Balanced, sweet, some acidity”
Well-extracted. You've dialled it in.
Fix: Lock in your settings and write them down.
Step 4: Fine-tune with yield
Once your grind is dialled, you can tweak the brew ratio to change the character of the shot without changing the grind:
- 1:1.5 (e.g. 18g → 27g)Ristretto - very concentrated, syrupy, intense sweetness. Less bitterness.
- 1:2 (e.g. 18g → 36g)Standard espresso - balanced, full flavour, classic.
- 1:3 (e.g. 18g → 54g)Lungo - more dilute, often brighter and more bitter. Good for milk drinks.
Common mistakes - and how to avoid them
- 1.Changing grind size and dose at the same time. Pick one variable and move it alone.
- 2.Not using a scale. Eyeballing dose leads to inconsistency. A cheap kitchen scale changes everything.
- 3.Ignoring freshness. Coffee that's past its peak simply won't dial in well - it goes flat. Use beans roasted within the last 4 weeks.
- 4.Skipping the purge after adjusting grind. Old grounds from the previous setting will skew your results.
- 5.Tamping unevenly. An uneven tamp creates channels where water takes the path of least resistance. Press straight down with firm, even pressure.
Now find beans worth dialling in.
Fresh beans make all the difference. Browse espresso-forward coffees from specialty roasters.