Three numbers define every espresso shot: how much dry coffee goes in (dose), how much liquid comes out (yield), and the ratio between them. Master these three numbers and you can replicate any shot, communicate precisely with other baristas, and troubleshoot changes systematically.
The Three Numbers
The formula is simple: Ratio = Yield ÷ Dose. An 18 g dose pulled to 36 g yield gives a ratio of 1:2. This is called a normale - the standard double espresso.
The Classic Ratio Categories
| Style | Ratio | Example (18 g dose) | Character |
|---|---|---|---|
| Ristretto | 1:1 – 1:1.5 | 18–27 g yield | Very concentrated, syrupy, sweet, low bitterness, short |
| Normale | 1:2 – 1:2.5 | 36–45 g yield | Balanced, full flavour, standard espresso |
| Lungo | 1:3 – 1:4 | 54–72 g yield | More extraction, lighter body, more bitter, longer |
| Allongé | 1:5+ | 90+ g yield | Very dilute, used for filter-style espresso on dialled light roasts |
How Ratio Affects Flavour
Increasing yield (pulling a longer shot) does two things simultaneously:
- It increases extraction - more water passes through, dissolving more compounds including later-extracting bitter ones.
- It decreases strength - the same amount of dissolved solids is now diluted in more liquid.
This is why the Espresso Compass shows yield as a diagonal move across both axes. A ristretto shot at 1:1 is high in strength but stops extraction early - only early-extracting acids and sugars come through, resulting in intense sweetness and no bitterness. A lungo at 1:3 has low strength but high extraction - every compound has been pulled, including bitter ones.
When to Change Yield vs When to Change Dose
Change dose when you want to permanently increase or decrease the amount of flavour going into the cup, or when switching basket sizes. Change yield when you want to fine-tune extraction level and strength within an existing setup.
Why You Should Always Weigh Output
Volume-based espresso (using the size of the cup or a timed pump stop) is notoriously unreliable. Crema varies massively - a light roast produces almost no crema, a medium roast can produce a thick foamy head. Crema is essentially gas bubbles, not liquid coffee. A 40 ml volumetric shot with heavy crema might only contain 28 g of actual liquid. Weigh the yield on a scale to know exactly what you pulled.
Ratio and Roast Level
Roast level has a strong influence on the ideal ratio:
- Light roasts: High density, high acidity, slower extraction. Often benefit from longer ratios (1:2.5 – 1:3) to ensure enough extraction, or even allongé-style for filter-profile espresso.
- Medium roasts: The sweet spot for classic espresso ratios. 1:2 to 1:2.5 gives balanced flavour.
- Dark roasts: Extract very quickly and become bitter fast. Shorter ratios (1:1.5 – 1:2) stop extraction before bitter compounds dominate. Some baristas use lower doses with dark roasts to further limit extraction.
The 1:2 Starting Point
If you have never tracked your ratio, start here: weigh your dose, pull until you have exactly double that weight in the cup, and taste. Adjust from there. If the shot is too strong and intense, try 1:2.5. If it is thin and bitter, try 1:1.8. The ratio is your first dial - grind size is the second.