Dialing in espresso is mostly a conversation between three numbers: how much dry coffee goes in, how much liquid espresso comes out, and how long the shot takes. The Espresso Extraction Calculator turns your dose and yield into a brew ratio, helps you set a target yield, and explains what your numbers can and cannot tell you.
Enter the dose and the weight of the finished espresso. Extraction time and a target ratio are optional. The calculator runs entirely in your browser.
Your Espresso Recipe
- Brew ratio
- 1:2
- Style
- Espresso / Normale-style
- Flow
- 1.29 g/s average flow (28 s)
What is an espresso brew ratio?
The brew ratio compares the weight of dry ground coffee to the weight of liquid espresso in the cup. An 18 g dose that produces 36 g of espresso has a 1:2 brew ratio. Many baristas weigh the beverage instead of measuring its volume, because crema makes volume unreliable.
Brew ratio is not the same as extraction yield. Extraction yield is the percentage of the coffee’s mass that dissolved into the cup, and measuring it requires a refractometer to read the concentration (TDS) of the espresso. This tool does not measure or estimate extraction yield or TDS; it describes the ratio and the flow of your shot only.
How to measure coffee dose and espresso yield
- Place your portafilter on a scale, tare it, and weigh the ground coffee you put in. That number is your dose.
- Place your cup on the scale and tare it. A scale that reads to 0.1 g is ideal.
- Start the shot and a timer together, and stop the shot when the scale reaches your target weight.
- Note the final weight in the cup (the yield) and the elapsed time.
- Enter the dose, yield, and time into the calculator.
Some people start the timer when the pump starts and others when the first drops appear. Either is fine as long as you do it the same way every time.
Understanding ristretto, espresso, and lungo
- Ristretto-style: roughly 1:1 up to just below 1:2. A shorter, more concentrated drink.
- Espresso or Normale-style: around 1:2, for example 18 g in and 36 g out. A common starting point for dialing in.
- Lungo-style: above 1:2, with 1:3 as one possible reference point. A longer, lighter-bodied drink.
These labels are descriptive. They vary between cafes, countries, and roasters, and none of them is a quality standard.
How grind size influences espresso preparation
A finer grind creates more resistance to the water, so the shot flows more slowly. A coarser grind flows faster. When you change the grind, the time it takes to reach the same yield changes with it, which is why many baristas keep the dose and target yield fixed and adjust the grind to arrive at a flow rate they like.
Dose also matters. Baskets are designed for a range of doses, so check the recommendation for your basket before changing it.
How to interpret extraction time
Time is a result of your recipe, not a goal in itself. Many espresso recipes finish in roughly 20 to 40 seconds, but a fast shot can taste great and a slow one can taste bad, depending on the coffee, grinder, and preparation. Use time as a clue: if a shot gushes or chokes, something about the grind, dose, or puck preparation is probably worth checking.
Time alone cannot confirm whether a shot is under-extracted or over-extracted. Taste the espresso and change one variable at a time.
Troubleshooting examples
| What you notice | Things you could try, one at a time |
|---|---|
| The shot tastes sour, thin, or salty | A finer grind, a longer yield (a higher ratio), or, if your machine allows it, slightly hotter brew water. |
| The shot tastes bitter, harsh, or dry | A coarser grind, a shorter yield (a lower ratio), or slightly cooler brew water. |
| The shot runs very fast | Check your dose and puck preparation, then try a finer grind. |
| The shot runs very slowly or chokes | Try a coarser grind and make sure the dose is not too high for your basket. |
| Shots are inconsistent | Weigh the dose and the yield every time, and keep your preparation routine consistent. |
Frequently asked questions
What brew ratio should I start with?
A 1:2 ratio is a common starting point, for example 18 g in and 36 g out. Some brewers use longer ratios for lighter roasts and shorter ones for darker roasts. Start at 1:2, taste, and adjust.
Does a 1:2 ratio guarantee a good shot?
No. The ratio tells you how much liquid you extracted from how much coffee. Grind, freshness, water, temperature, and preparation all affect the taste.
Should I start timing when the pump starts or when the first drops appear?
Either works. Choose one method and use it consistently so your numbers are comparable from shot to shot.
Why does my machine’s volumetric button not match my scale?
Volumetric settings measure the volume of liquid, which includes crema. A scale measures weight, which is a more consistent way to describe a recipe.
Can this calculator tell me whether my shot is under-extracted?
No. Extraction yield can only be calculated from a measurement of the concentration (TDS) of the espresso. This tool calculates brew ratio and flow, so it can suggest things to try but cannot give a verdict.
What dose should I use?
It depends on your basket and your machine. Check the recommended dose range for your basket and start in the middle of it.
Related guides on JoinWorky
- Coffee grind size explained from coarse to fine – how grind size shapes flow and taste
- How to choose a coffee grinder for the brewing methods you use – matching a grinder to your brewing style
- Burr and blade coffee grinders – why grind consistency matters
- Manual or electric coffee grinder – choosing a grinder for your routine
- Why freshly ground coffee can make a noticeable difference – freshness and grinding at home
More coffee tools
- Coffee Brewing Ratio Calculator – work out coffee and water amounts for any brewing method.
- Coffee Brewing Temperature Guide – find a starting water temperature by method and roast.
- All JoinWorky coffee tools – the full directory.
About these categories
The ratio categories are descriptive starting points, not strict definitions, and the guidance on time is deliberately cautious. Espresso results depend on the coffee, grinder, machine, and your preparation, so use the numbers as a record of what you did and a prompt for what to try next.