I  Cold Brew

Cold brew, measured

Cold brew, worked out to the gram.

Ratios from the makers' own instructions, research re-plotted from the papers, and gear chosen from spec sheets.

Ratio calculator

12 fl oz glasses

Ratio
1:4
Coffee
237 g
Water
946 g

Concentrate, cut 1:2 with water when you pour.

Illustrated cross-section of a lidded glass jar of steeping cold brew: coarse grounds settled at the bottom, the liquid shading from pale amber at the top to deep brown at the grounds, measurement ticks on the glass, ice cubes beside it.
Fig. 1 · Immersion jar, mid-steep (illustration)

01 · Start here

Pick a starting point.

All gear guides →
Illustration of a generic glass cold brew pitcher with its filter basket lifted out, a plain paper coffee bag, a kraft gift box with twine and a small hand grinder in cutaway.

Gift season

Cold brew gift guide

Gifts for the cold brew drinker, sorted by price: makers, grinders, beans, and subscriptions that keep arriving.

Research roundup22 products

  1. First batch

    Cold brew starter kit

    The minimum kit for a first batch, no grinder needed, and what to add later.

    Research roundup9 products

  2. Makers

    Best cold brew makers

    Pitchers, filter-and-drain brewers and electric machines, grouped by how they brew.

    Research roundup11 products

02 · The Lab

Questions, answered from the data.

All 5 Lab files →
  • 2 sourcesLiterature review

    Does grind size matter for cold brew?

    7.06%

    Extraction yield, medium grind (Huila, 14 h)

    Depends what you measure. Caffeine barely cared. In a filter bag, coarse grounds extracted about twice as much as medium. The bean mostly changed acidity.

    Source: Cordoba et al. 2019

  • 2 sourcesLiterature review

    How long should cold brew steep?

    6–7h

    Caffeine and 3-CGA level off

    Caffeine levels off around 6–7 hours at room temperature. Everything else keeps dissolving, and in one tasting, 14 hours beat 22.

    Source: Fuller & Rao 2017

  • 1 sourceLiterature review

    What actually changes between cold brew and a French press?

    2.95% TDS

    Strength, room-temp cold brew (23 °C, 8 h)

    At room temperature, 8 hours matched the French press for strength and caffeine, with higher pH and less titratable acid. The fridge brew came out weaker.

    Source: Wang & Lim 2023

03 · Recipes

Drinks built from one batch.

All 9 recipes →