CremaTheory

Strength adjuster

If a brew came out too strong, adding water fixes it without changing its extraction, because only the concentration moves. If it came out weak, water can't help. You need something stronger, like espresso or a concentrate. Either way it's a mass balance on the dissolved coffee, so the answer is exact.

Add –

How it's worked out

  1. TDS% is a mass fraction, so the maths is in grams. If you enter millilitres, they are treated as grams. Filter coffee is only about 0.5% denser than water, so the error is small. Espresso is denser, so weigh it.
  2. Added water counts as 0% TDS. You zero the refractometer on your brew water, so its minerals are already outside the reading.
  3. Extraction yield is set at brewing. Diluting afterwards changes strength only. Mixing in a different coffee blends two extractions, and this calculator doesn't track that.