Coffee strength is measured as TDS, the percentage of dissolved solids in the cup. It describes how concentrated the brew tastes, separate from how much was extracted.
TDS (%) = (Solids ÷ Beverage) × 100
What the terms mean
| Symbol | Meaning |
|---|---|
| TDS | Total dissolved solids, percent |
| Solids | Dissolved coffee mass, in grams |
| Beverage | Final beverage mass, in grams |
Worked example
If 5.2 g of coffee dissolved into a 400 g cup, the strength is (5.2 ÷ 400) × 100 = 1.3% TDS.
The brewed target. Brewed coffee usually tastes best around 1.15 to 1.35% TDS. Espresso is far higher, often 8 to 12%.
FAQ
Is TDS the same thing as extraction yield? No. TDS (total dissolved solids) measures how strong the final cup tastes, while extraction yield measures what percentage of the coffee grounds actually dissolved into the water. Two very different ratios and grinds can hit the same TDS through different extraction yields.
See the Coffee Strength Calculator and the Extraction Yield Formula.