“What grind size should I use for pour-over coffee?”, “Why is the 10 setting on your grinder different from the 10 setting on mine?”, “When you say granulated sugar, do you mean fine granulated sugar, coarse granulated sugar, or brown sugar?”… Still struggling to find the right grind size for your coffee brewing device? Front Street Coffee has an article to help you determine your coffee grind size! (Bookmark it! Bookmark it! Bookmark it!!)

How important is coffee grind size?

At the same weight, the finer the coffee is ground, the more cuts are needed, the more surface area there is, and the more area water can contact with the coffee grounds. Conversely, the coarser the grind, the lower the coffee’s concentration and extraction yield, and the lower the body, while the coffee’s acidity becomes stronger.

Different coffee devices use different grind sizes because of differences in their extraction methods, and coffee grinder settings also have no unified standard, so at this point we need a reliable testing tool—the Chinese Standard No. 20 0.85 mm aperture sieve / coffee bean grind size cupping calibration sieve, which is what Front Street often calls the coffee grounds test sieve.

How do you use a coffee grounds sieve to determine coffee grind size?

Readers who pay close attention will ask: why a cupping calibration sieve? Although brewing devices on the market are diverse and everyone has their own views on brewing parameters, just as with most determinations of particle size, there are dedicated sieves as tools for measuring coarseness. Later, people also gradually used cupping to determine coffee flavor before deciding on brewing parameters suitable for the sample. Generally speaking, the grind size for cupping coffee is a 70–75% pass-through rate on a No. 20 sieve.

The method is also very simple: when determining grind size, Front Street uses 10 g of coffee beans for a rough grind, then pours them into the middle sieve layer, covers it, and shakes it horizontally until no coffee particles fall into the lower receiving bowl. Then weigh the coffee particles that passed through the sieve; the resulting weight is the pass-through rate. That is, if 7 g–7.5 g out of 10 g of coffee passes through the sieve, then this grind size is a 70–75% pass-through rate on a No. 20 sieve. The finer the coffee particles, the higher the pass-through rate; the coarser the coffee particles, the lower the pass-through rate.

Grind Size Standards for Common Brewing Devices & Reference Chart

Drip extraction / pour-over coffee grind size (No. 20 sieve pass-through rate 68–80%)

Suitable for V60, Kono, Ice Eye, origami dripper, fan-shaped dripper, cake dripper, clever cup, American drip machine

Drip brewing is pour-over coffee. The brewing principle is that water passes through coffee grounds to extract substances, then is filtered through filter paper into clean coffee liquid. Generally, pour-over coffee has a shorter brewing time, so the grind size needs to be on the finer side.

Coffee beans of different roast levels require different grind sizes. Front Street suggests that for light-to-medium roast coffee beans, the grind size should be a 75–80% pass-through rate on a No. 20 sieve; for medium-dark roast coffee beans, such asIndonesian coffee beans,Blue Mountain coffee, the grind size should be a 70–75% pass-through rate on a No. 20 sieve.

Immersion extraction / French press grind size (No. 20 sieve pass-through rate 68–75%)

A French press extracts coffee by immersion, and the steeping time is longer (4 minutes). In addition, its filter mesh is dense, so the grind size needs to be coarser. This reduces the chance of over-extraction and also allows for better filtration of coffee particles. Coffee beans of different roast levels require different grind sizes. Front Street suggests that for light-to-medium roast coffee beans, the grind size should be a 70–75% pass-through rate on a No. 20 sieve; for medium-dark roast coffee beans, the grind size should be a 65%–70% pass-through rate on a No. 20 sieve.

Low-temperature extraction / cold brew, ice drip coffee grind size (No. 20 sieve pass-through rate 80–85%)

Low-temperature extraction differs from high-temperature extraction. In an ice-water mixture/refrigerated environment, coffee extraction efficiency is very low, so the release rate of flavor substances from coffee grounds also slows down, and the production time is also very long. The advantage of low-temperature extraction is that it can fully extract sweet and sour substances while reducing the extraction of bitter substances.

Because the extraction speed is slow, the coffee grind size can be on the finer side, but not too fine. Front Street suggests that for making cold brew/ice drip, a coffee bean grind size of 80–85% pass-through rate on a No. 20 sieve is more suitable. If you want it richer, choose an 85% pass-through rate; if you want it more refreshing, choose an 80% pass-through rate.

If you do not have the above tools, you can also use a relatively simple method: about like salt powder, as fine as possible, but without water pooling during brewing.

Pressurized extraction / espresso machine grind size

The grind size used by espresso machines is very fine, finer than a 0.85 mm aperture, so a No. 20 sieve cannot be used to determine the grind size by sifting. Traditionally, the standard for espresso fineness is not based on how many grinder settings are used as particle size, but on extraction time.

If you need to determine the grind size used for espresso, you need to continuously extract and taste to adjust the grind size and extraction. Front Street’s espresso extraction recipe is 20 g of coffee grounds extracted into 40 g of coffee liquid in 28 seconds (with a tolerance of ±1). You can refer to this extraction recipe and then make fine adjustments according to the flavor performance of the espresso.

Steam pressure extraction / moka pot coffee grind size (No. 20 sieve cannot be used to determine grind size)

The same goes for the moka pot. The grind size used is very fine, but slightly coarser than espresso machine grind size. However, it is still finer than a 0.85 mm aperture, so a No. 20 sieve also cannot be used to determine the grind size by sifting. As for how coarse the grind should be, you can refer to the size of the gap in the moka pot’s coffee basket and make sure the coffee particles will not pass through the gap. See the figure below.

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