Strength

Strength is how concentrated your coffee tastes: thin and watery versus thick and intense. Technically it is the share of dissolved coffee solids in the liquid, measured as total dissolved solids (see tds) and usually given as a percentage. Filter coffee commonly lands around 1.2 to 1.5 percent TDS; espresso is far more concentrated, often 8 to 12 percent.

The key idea, and a common point of confusion, is that strength is not the same as extraction yield. Extraction yield is how much of the coffee’s mass you dissolved out of the grounds (the typical sweet spot is roughly 18 to 22 percent). Strength is how much of that ended up packed into each sip. You can have a strong cup that is under-extracted and sour, or a weak cup that is over-extracted and bitter. They are two separate dials.

What controls strength most directly is your brew ratio: more coffee per unit of water makes a stronger cup, more water makes a weaker one (see coffee-to-water-ratio). Grind, time, and temperature mostly move extraction yield, which shifts flavor balance. Adjust strength with ratio first, then chase flavor with the other dials.