Whether you’re grinding your own coffee beans at home or buying them pre-ground, it’s important to pay attention to the size of the ground coffee particles, or “grind size”, when brewing your coffee.
Grind size is one of the most important contributors to how strong a cup of coffee is brewed, and how it tastes.
Here, we’ll go over the basic guidelines around grind size for different at-home brewing methods, and explain some of the science around it… but keep in mind, it all comes down to your own personal preference.
Feel free to use this information as a starting point, then adjust to your liking!
Grind size ranges from very fine to very coarse.
At its smallest size, ground coffee can resemble flour and is traditionally used for Turkish coffee, which is strong, unfiltered, and usually brewed with sugar.
At the other end of the spectrum, coffee that is ground very coarsely can resemble sand or breadcrumbs. This would be used to brew cold brew coffee or French Press coffee.
So why do certain brew methods call for different grind sizes? It all comes down to extraction.
Finely ground coffee particles have less surface area, and therefore flavours and aromas are extracted from them more quickly, once hot water is added. This can lead to over-extraction, which causes unpleasant bitterness and aggressive flavours.
Adversely, coffee ground too coarsely takes longer to extract, therefore risking under-extraction… which leads to sourness, and underdeveloped flavours.
Espresso, for example, is a very fast brewing process (20-25 second brew time). Therefore, you want to use finely ground coffee.
French Press coffee takes a lot longer to brew (around 4 minutes), so you’d want to use coffee ground coarser. Think of grind size on a scale from bitter to sour:
Here are some quick guidelines for ideal grind sizes using various home brewing methods:
As I mentioned earlier, these are simply guidelines, and it all comes down to what you prefer. Knowing these details will help you brew your coffee to your tastes.
Try using coffee grounds slightly finer than usual if you prefer a stronger cup! And if your French Press coffee or cold brew coffee is coming out a little strong or bitter, try grinding your coffee a little coarser next time.
If you’re buying your coffee pre-ground, you’ll now know that if it was ground for use as espresso, it will come out very bitter and over-extracted if brewed using a drip brewer or french press -- and vice versa.
Author John Ohrn