How to Make Powder Coffee by Adjusting Espresso Grind Size

Espresso is ground much finer than pour-over, and the adjustment window is narrow: a fraction of one click on the dial can push flow rate and flavor to opposite extremes. Begin by judging the grounds by feel, aiming for something close to flour-like fineness. Then use the common baseline of a 1:2 coffee-to-water ratio and a 20 to 30 second extraction time to decide whether to grind coarser or finer.

Treat that formula as a quick positioning tool, not the final answer. Once the shot falls inside the time range, fine-tune using flavor cues such as burnt bitterness, crema color and the length of the finish. The ratio can also be widened to between 1:1.5 and 1:2.5 to suit a particular bean. Grind particles finer than fine salt, and change the setting in small steps rather than large jumps.

Espresso is ground much finer than pour-over, and its adjustment window is extremely narrow—often a difference of just a fraction of a click can push flow rate and flavor to two opposite extremes. This article starts with how to determine the grinding range: first use the feel of the grounds to judge whether they are close to flour-like fineness, then apply the common formula of a 1:2 coffee-to-water ratio and 20–30 seconds for dialing in, and decide whether to grind coarser or finer based on whether the flow is fast or slow. The article further explains that the formula is only a quick positioning tool; in the end, you need to fine-tune based on flavor cues such as burnt-bitterness, crema color, and the length of the finish, and even widen the ratio to between 1:1.5 and 1:2.5 to find the setting that truly suits that particular bean.

Anyone who makes coffee knows that grind size is one of the key variables determining success or failure. If the setting is wrong, or the ground particles vary in size, the extraction can easily end up under- or over-extracted. Compared with methods like pour-over and cold brew, espresso requires much finer particles and more precise adjustments to keep the espresso's flavor within the ideal range.

How fine should espresso coffee actually be ground?

When discussing pour-over grind size, Front Street Coffee habitually uses the Chinese No. 20 standard sieve to see how much coffee powder passes through a fixed aperture, judging whether the particle size is appropriate. But espresso is a pressurized, short-time extraction, where every detail is magnified exponentially—good flavors are magnified, and flaws are magnified just the same—so the demands on grinding are especially strict. Its particles are finer than fine salt; the naked eye can't tell the grind size or judge uniformity, and calibrating with a sieve is even more impractical.

If the coffee is ground a little finer, the resistance of water passing through the bed increases, easily causing over-extraction; conversely, if it's a little coarser, water passes through more easily, leading to under-extraction. And such an obvious difference may come from a change of just 0.1 on the dial. Therefore, in actual brewing, we usually judge whether the grind size falls in the right range by observing the espresso's flow rate and tasting the flavor.

Step One: First Define the Suitable Grinding Range

When you get a bag of unfamiliar beans and want to brew them well, the first thing is to find the right grind size. If the equipment is new to you and you don't know which setting range is suitable, you can first grind a small amount of beans at different settings to test. When the coffee powder feels like flour—soft to the touch, with no gritty coarseness—the fineness is about right.

Next, you can apply the common espresso formula to extract. Front Street Coffee suggests a coffee-to-water ratio of 1:2, meaning 1 gram of coffee yields about 2 grams of espresso, with the time controlled at 20–30 seconds. For example, Front Street Coffee uses a 20-gram capacity basket, so you dose 20 grams of coffee and aim for 40 grams of yield. If it takes less than 20 seconds, the flow is too fast; if it exceeds 30 seconds, the flow is too slow.

A fast flow means the water contacts the coffee grounds for too short a time, and the taste tends to be weak or sour, so you need to grind finer. Adjusting the setting relies heavily on accumulated experience: if you're within 5 seconds of the target time, you can move 0.2 clicks at a time; if the gap is large, be bolder and adjust 0.5–1 click each time. Even if you jump from over-time to too-fast all at once, it helps you lock in an approximate setting range, then gradually narrow it down. Conversely, a flow that's too slow means the coffee is too fine, water struggles to penetrate the bed, and the taste easily turns bitter and astringent, so you need to grind coarser.

How Do You Determine the Truly Correct Grind Setting?

The formula mentioned earlier only helps us quickly find a usable grinding range; it doesn't mean the espresso extracted with these parameters will necessarily taste good. Ultimately, you still need to judge whether the extraction is on target based on the characteristics of the beans themselves and the actual taste.

If the espresso tastes distinctly burnt and bitter but the strength is still moderate, it may be that the extraction time is too long and too many bitter compounds have been released, so you can grind slightly coarser. If the crema on the surface is pale in color and thin in texture, it may be that too much of the tail end has been extracted; you can reduce the yield—that is, extract less—and it's suggested to raise the coffee-to-water ratio to 1:1.5–1:1.7. If the espresso has rich flavor but a very short finish, you can extract a bit more and try adjusting the ratio to 1:2.5.

In the end, extraction formulas are only a reference. If you're boxed in by them, it actually becomes harder to dial in good flavor, and you end up repeatedly adjusting the grind and wasting beans for nothing. 1:2 isn't necessarily the golden ratio for a given bean; sometimes 1:1.7 tastes better, and sometimes 1:2.5 is what makes it shine. Nor must you rigidly stick to 25–30 seconds—maybe 36 seconds or 24 seconds is when this bean performs best. Front Street Coffee is daily café production, and parameter adjustments rely on accumulated daily experience. If you make few cups at home and find it hard to grasp, Front Street Coffee suggests recording the parameters and flavor each time, and summarizing the relationship between extraction parameters and flavor performance, so you can dial in faster and reduce unnecessary waste.

For professional coffee knowledge exchange and more coffee bean information, please follow Coffee Workshop (WeChat public account: cafe_style)

For more specialty coffee beans, please add the private WeChat of Front Street Coffee (FrontStreet Coffee), WeChat ID: qjcoffeex

The above content is compiled by CoffeeHunters, a coffee news website.