Espresso tutorial: How to optimize an espresso?

A common question many people ask themselves is, how can I get the best out of the coffee beans I have? First and foremost, certain criteria must be met.

Making espresso can be a challenge. Brewing a cup of coffee under high pressure in about 30 seconds is actually pretty extreme—and can be frustrating for many. Especially when it comes to repeating that perfect shot. Most of us have been there: you pull an amazing espresso, but when you try to make another, something goes wrong.

Many assume all espresso beans are more or less the same. But volume, moisture, temperature, variety, roast level, and age—all of these factors affect how your espresso turns out. Often, we brew espresso by guesswork: grind some coffee, fill the portafilter, and hope for the best—without weighing anything. This usually leads to inconsistent results. A single gram more or less can make a big difference in taste.

That’s why certain criteria are essential if you want to repeat that great cup. You have to be consistent—without consistency, it’s hard to know what went wrong. And yes, some basic equipment is necessary.

Equipment

We'll start with the equipment you need to make espresso. Of course, that's not all the equipment you need, some are basic while other tools can simplify the process for you.

It doesn’t have to be anything fancy—but it should be a manual machine, like a Gaggia or Rancilio Silvia.

Make sure the machine is relatively clean, meaning it’s not filled with old coffee residue in the group head.

Check what type of filter basket is in the portafilter—is it a single or a double?
Look for the capacity: 14g, 18g, or something else.
This is often listed in the manual, or you can easily find it with a quick Google search.
Your coffee grinder should be of decent quality, but it doesn’t need to be expensive.

Make sure it’s capable of grinding for espresso. Many grinders can't grind fine enough for proper espresso extraction.

It should be consistent, producing uniform grounds to avoid uneven extraction.

Ideally, choose a grinder with stepless adjustment, which lets you fine-tune the grind precisely rather than jumping between preset steps.

If your grinder has stepped settings, you can still compensate by adjusting the dose.
For example, if one grind setting is too coarse and the next is too fine, try increasing the amount of coffee slightly to balance the extraction.
The most underrated tool in coffee brewing—no matter the method—is the coffee scale.

Invest in a scale that measures in 0.1-gram increments. This is especially crucial for espresso, where even the smallest variation can impact the final result.

Make sure your scale is consistent and accurate. Many inexpensive models are unreliable and tend to “drift” or fluctuate between numbers, making it hard to measure and adjust your doses precisely.

Having a built-in timer is a nice bonus, but not essential.
Make sure your tamper fits your portafilter properly—a good fit is key to even extraction. Any type of tamper can work, but if you want to be extra consistent, consider getting a calibrated tamper.

A calibrated tamper applies the same amount of pressure every time, so you don’t have to worry about pressing too hard or too lightly.
To evenly distribute the coffee and prepare it for tamping, you can use a Leveler Distributor.
This tool helps create a flat, consistent surface in the portafilter—perfect for an even tamp and better extraction.
Ground coffee tends to clump together. These clumps can lead to channeling in the coffee puck—where water finds paths of least resistance, resulting in uneven flow. This often compromises flavor, as some areas are over-extracted while others are under-extracted.

To prevent this, you can use the WDT (Weiss Distribution Technique). This involves using fine needles or tools to break up clumps and evenly distribute the grounds before tamping, helping ensure a uniform extraction.
A dosing ring gives you better control and less mess. While it's not essential, it helps prevent coffee from spilling over the edge of the portafilter during grinding.

If you're using WDT, a dosing ring becomes especially helpful—it keeps all the grounds contained while you break up clumps and distribute evenly.

For added convenience, look for a magnetic dosing ring—it stays securely in place and won’t shift or fall off during prep.

Preparation

The most important thing when dialing in espresso is to keep certain parameters consistent.

Decide How Much Coffee to Use in the Portafilter

Most people use a double espresso basket. The most common dose for a double is 18 grams of ground coffee. However, some baskets—like the stock basket on the Rancilio Silvia—are designed for 14–16 grams.

When a basket is marked with a range like 14–16g, it means:

14g is suited for dark roasts

15g for medium roasts

16g for light roasts

That’s because darker roasts take up more space and are oilier, which makes it harder for water to pass through evenly—so you need less coffee. Precision baskets like those from VST will have the exact recommended dose printed on the side.

Whatever amount you choose—stick to it. It’s crucial to use a scale that measures down to 0.1 grams, because even a 0.5–1g variation can noticeably affect the taste.

TIP:
Always measure coffee by weight, not volume. Volume can vary depending on bean type, roast level, moisture, and more. If you rely on volume, you won’t be consistent—and you won’t be able to repeat that great shot.
VST Presision filter
Double espresso filter
Filter for one shot espresso
Light Roast
Medium Roast
Dark Roast
When it comes to espresso, the most common brew ratio ranges from 1:1.5 to 1:2.5.
For example, a 1:2 ratio means using 18g of ground coffee in the portafilter and aiming for 36g of espresso in the cup.

The ratio you choose depends on the type of coffee and roast level:

Light roast: 1:2.5

Medium roast: 1:2

Dark roast: 1:1.5

Once you’ve decided on your target output, stick to it consistently. This consistency is key to dialing in your espresso and understanding how other variables affect the taste.
Light Roast
Medium Roast
Dark Roast
Coffee Is Sensitive to Temperature
Espresso is highly affected by brewing temperature. The ideal range is between 86°C and 95°C. The darker the roast, the lower the temperature should be.

Recommended Starting Points:

Light roast: 92–95°C

Medium roast: 89–92°C

Dark roast: 86–89°C

The best option is, of course, to use an espresso machine with a temperature display or control. But not everyone has access to that.

If your machine doesn’t have a temperature readout, you can use a technique called flushing. That means letting hot water run through the group head before inserting the portafilter.
Often, steam or a hissing sound comes out first—this indicates the water is too hot. Let it run for 5–10 seconds to stabilize the temperature before brewing.

Try to stay as consistent as possible every time you pull a shot.
Your puck preparation routine can make a big difference in your results. The more consistent and precise your puck prep, the easier it becomes to repeat a great shot—and to adjust just one variable at a time.

What matters most is that you do it the same way every time. That way, you'll know exactly what’s changed from shot to shot—and what’s affecting the outcome.
Tamping is Often Overdone
Many people tamp with their full body weight—but that’s completely unnecessary. You only need about 12 kg (26 lbs) of pressure, which is actually quite light.

How to Tamp Properly:

Place the tamper in the portafilter as straight as possible.

Rest your hand on top, with one finger on each side for control.

Press gently and evenly—when you feel resistance, you're done.

Wipe off any loose grounds from the rim of the basket.

TIP:
Avoid tapping the tamper against the side of the portafilter—this can cause cracks in the puck and lead to channeling, which results in uneven extraction.

Let´s make coffee!

Now that we have clarified all fixed parameters, we start the process.

Start with a warmed-up espresso machine filled with fresh cold water.
The most important thing when dialing in espresso is to keep certain parameters consistent.

The time window we work with is typically between 25–35 seconds. Within that time, you should aim to extract the yield you've decided on—for example, 18g in, 36g out. That means 36 grams of espresso in 25 to 35 seconds.

If you're not satisfied with the result within that time frame, you can try pushing the shot a bit longer to see if it improves.

If your hopper is already filled with coffee beans, you can skip straight to step 2.

Now, weigh out the amount of coffee you've decided to use—e.g., 18g. It doesn't have to be exact; 17.8g or 18.2g is perfectly fine. But aim for around 18g as your target.
Light Roast
Medium Roast
Dark Roast
Set your grinder so that you expect to hit a 1:2 ratio in 25 seconds. In other words, if you have 18g of coffee in the filter, you should aim to get around 36g of espresso in 25 seconds.
Weigh the ground coffee. If there’s too little, grind a bit more. If there’s too much, remove the excess.
This is when you should use the tools you have available. If you only have an espresso tamper, try to distribute the coffee evenly in the portafilter before tamping by gently tapping the sides with your hand. The better the puck is prepared, the more evenly the water will flow through it—and the better the coffee will taste.
Place your coffee scale under the cup on your espresso machine. Tare the scale and reset the timer if it has one. If your scale doesn’t include a timer, you can use the stopwatch on your phone instead.
Press the brew button on your machine at the same time you start the timer—either on your scale or your phone.
You should now aim for a 1:2 ratio within 25 seconds.
If you don’t get the target amount in the cup (e.g., 36g from 18g of ground coffee) in that time, you’ll need to adjust your grinder:

If it took less than 25 seconds, adjust the grind finer.

If it took more than 25 seconds, adjust the grind coarser.
Once you've hit 25 seconds, it's time to start dialing in for taste. Begin at the low end—25 seconds—and work your way upward.

Go back to Step 1, but this time, adjust the grind slightly finer than your last setting. This will slow the flow of water, increasing the extraction time.

Repeat Steps 1–6 multiple times, adjusting a bit finer each time until you’re happy with the result.
If the flavor starts turning bitter and lingers at the back of your throat, you’ve likely gone too fine for this coffee. In that case, step back—grind slightly coarser—until you find the sweet spot.

If you change any fixed parameter—like increasing the dose from 18g to 19g, switching coffee beans, or adjusting any other constant—you'll need to start the process over again, beginning at 25 seconds.

Espresso tutorial: How to optimize an espresso?

Equipment

Preparation

How to Tamp Properly:

Let´s make coffee!

Now that we have clarified all fixed parameters, we start the process.