Espresso is not a coffee bean, a roast level or a dark colour. It is a brewing method: about nine bars of pressure forcing hot water through a compacted bed of finely ground coffee in roughly half a minute.
That combination of pressure and speed is what produces the texture, the crema and the concentration you cannot get any other way. It is also what makes espresso unforgiving. In a V60 a small mistake gives you a slightly worse cup. In espresso it gives you something undrinkable.
The good news is that there are only four variables, and only one of them moves day to day.
The four variables
Dose - what goes in
18 g for a standard double basket. Weigh it. Baskets are more forgiving than people think, but consistency is everything: if the dose changes, every other number you have dialled in becomes meaningless.
Yield - what comes out
36 g in the cup, which is a 1:2 ratio. This is the modern default and a good place to start for almost any coffee. Lighter roasts often want 1:2.5 or even 1:3 to extract properly; dark roasts are usually better shorter, at 1:1.5 to 1:2.
Time
25-30 seconds from the first drop. Time is not something you set - it is something you observe. It tells you whether your grind is right.
Grind
Fine, roughly like icing sugar. This is the only variable you should be adjusting once the others are fixed, and you will adjust it constantly - as the coffee ages, as the humidity changes, as you open a new bag.
| Variable | House setting | When to change it |
|---|---|---|
| Dose | 18 g | Only when changing basket size |
| Yield | 36 g | By roast level and taste |
| Time | 25-30 s | Never directly - it is an outcome |
| Grind | Fine | Every time the shot runs off target |
Reading a shot
The first drops should appear at 8-12 seconds. Much earlier and the grind is too coarse; much later and it is too fine.
The stream should come out dark and thick, then lighten steadily to a honey colour and finally to pale blonde. It should look like warm honey falling, not like water and not like a dripping tap.
If you see the stream split into several thin jets, or one side of the basket running faster than the other, that is channelling - water finding a low-resistance path through the puck instead of extracting evenly. The cause is almost always distribution or an uneven tamp, not the grind.
Fixing a bad shot
| The shot tastes | That means | Do this |
|---|---|---|
| Sour, sharp, salty | Under-extracted | Grind finer |
| Bitter, dry, hollow | Over-extracted | Grind coarser |
| Thin and weak, ran fast | Grind too coarse | Grind finer, check your dose |
| Harsh, ran very slow | Grind too fine | Grind coarser |
| Uneven, both sour and bitter | Channelling | Improve distribution, tamp level |
| No crema at all | Stale coffee | Use coffee 7-21 days from roast |
Change one thing, pull another shot, taste again. Two changes at once and you have learned nothing. There is a full walkthrough in How to Dial in Espresso at Home.
The grinder matters more than the machine
This is the single most useful thing anyone can tell you about home espresso: if you have a fixed budget, put it in the grinder.
Espresso needs a grind fine enough to build resistance against nine bars of pressure, and uniform enough that the water passes through evenly. A cheap grinder cannot do the second part. It produces a wide spread of particle sizes, the water races past the boulders and hammers the fines, and you get a shot that is sour and bitter at the same time - a fault no amount of adjustment will fix.
A grinder with a fine, repeatable adjustment - stepless or with very small steps - is what makes dialling in possible at all. See our grinders and machines.
Freshness and which coffee to use
Espresso is the method most sensitive to roast date. Too fresh - under 5 days - and the coffee is still degassing so violently that the shot gushes and tastes sharp. Too old - past a month - and the crema collapses and the cup goes flat.
The window is roughly 7 to 21 days from roast, and it is the reason we print the roast date on every bag and ship within 24-48 hours of roasting.
Our Espresso Blend is built to be forgiving - sweet, chocolatey and stable across a range of grind settings, which makes it a good coffee to learn on. When you want to push further, the single origins in our espresso collection will show you far more, and demand far more.
Espresso questions, answered
What is the standard espresso recipe?
18 g of coffee in, 36 g of liquid espresso out, in 25-30 seconds at 92-94 ºC. That is a 1:2 ratio and it works as a starting point for almost any coffee.
What grind size is espresso?
Very fine - roughly the texture of icing sugar, just short of flour. It has to be fine enough to resist nine bars of pressure, which is finer than any other brewing method uses.
Why is my espresso sour?
Under-extraction: the water passed through too fast to dissolve enough. Grind finer. If it is still sour at 30 seconds, check your dose and make sure the coffee is not more than a month past roast.
Why is my espresso bitter?
Over-extraction: the water spent too long in the puck, or the grind is too fine. Grind coarser and pull it shorter. Very dark roasts also taste bitter regardless of technique.
How long should an espresso shot take?
25 to 30 seconds from the first drop, for a 1:2 ratio. Time is a symptom rather than a setting - if the shot is outside that window, adjust the grind and pull again.
Do I need a special espresso roast?
No. Any coffee can be brewed as espresso. Roasts sold as espresso are simply developed a little further for sweetness and body under pressure, which makes them more forgiving. Light filter roasts make excellent espresso but need a longer ratio and a finer grind.
Can I make espresso without an espresso machine?
Not really. A Moka pot reaches 1-2 bars and an AeroPress® well under one, against the 9 bars espresso needs. Both make excellent strong coffee that works in milk drinks - just not espresso.
Keep going
Dialling in is a skill, and it takes a few wasted shots to build. Work through How to Dial in Espresso at Home next, and read up on grinding while you are at it.
If you are not ready for a machine, the Moka pot gets you a strong, concentrated cup on any stove for a fraction of the money.
