I  Cold Brew

Tool · Calculator

Cold brew ratio calculator

Say how much you want to drink. Get the coffee and water to weigh out, what comes off the grounds, and what a serving costs. Your settings live in the link, so you can send them to someone.

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Coffee for this batch · Trade Coffee

Cold Brew Coffee Subscription

Trade's cold brew offer has a Cold Brew grind on its menu and ships every 1 to 6 weeks, and you can pause or skip. For one bag with no commitment, Equator's Cold Brew Blend comes in a Coarse Grind (Cold Brew) option, 12 oz (340 g).
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Specs: manufacturer, checked 2026-10-04

Alternatives

How to use it

  1. Pick a style. Concentrate is brewed strong and cut with water when you pour. Ready to drink is brewed at the strength you'll drink.
  2. Say how much. Enter servings and a serving size, or a total volume. Edit one and the other follows.
  3. Set the ratio. The slider is water per gram of coffee, by weight. A maker's own recipe is one tap away under the slider. In concentrate mode, the dilution slider is how much water you add at the glass.
  4. Weigh it. Coffee in grams, water in grams (1 g of water is 1 mL). The ounce figures are there if your scale prefers them.
  5. Steep. OXO and Filtron say 12 to 24 hours. Toddy says 8 to 24 hours. Hario's ready-to-drink pot takes about 8 hours in the fridge.

The calculator doesn't pick a steep time. A 2017 study in Scientific Reports found caffeine and one chlorogenic acid reached equilibrium in 6 to 7 hours at room temperature (Fuller & Rao, 2017). Those are two compounds, not the whole cup, so it doesn't settle how long to steep. The Lab has what the steep-time research does and doesn't show.

Cold brew ratio chart

Common batch sizes, finished drink. Ready to drink is brewed at 1:14.4. Concentrate is brewed at 1:4 and diluted 1:2, so the Makes column is the concentrate to brew first. Built from the same numbers as the calculator, so the two always match.

Finished drinkReady to drink 1:14.4Concentrate 1:4, diluted 1:2
CoffeeWaterCoffeeWaterMakes
12 fl oz355 mL29 g1 oz412 g13.9 fl oz59 g2.1 oz237 g8 fl oz118 mL4 fl oz
1 qt946 mL76 g2.7 oz1,099 g37.1 fl oz158 g5.6 oz631 g21.3 fl oz315 mL10.7 fl oz
2 qt1,893 mL153 g5.4 oz2,198 g74.3 fl oz316 g11.1 oz1,262 g42.7 fl oz631 mL21.3 fl oz
1 gal3,785 mL305 g10.8 oz4,395 g148.6 fl oz631 g22.3 oz2,523 g85.3 fl oz1,262 mL42.7 fl oz

Where the numbers come from

The ratio presets are the makers' own recipes, read from their instructions. Concentrate:

  • OXO: 284 g (10 oz) coffee to 1,200 mL (41 fl oz) water, 1:4.2, diluted 1:2, steeped 12 to 24 hours.
  • Toddy: 340 g (12 oz) coffee to 1,893 mL (64 fl oz) water, 1:5.6, diluted 1:2, steeped 8 to 24 hours.
  • Filtron: 454 g (16 oz) coffee to 1,893 mL (64 fl oz) water, 1:4.2, steeped 12 to 24 hours.

Ready to drink:

  • Hario: 80 g (2.8 oz) coffee to about 1,150 mL (39 fl oz) water for a 1,000 mL pot, 1:14.4, refrigerated about 8 hours. Hario specifies dark roast and a medium-fine grind, finer than the coarse grind most concentrate recipes use, and says coarse coffee brews weak.

Yield is an estimate. The calculator assumes the grounds keep 2 g of water per gram of coffee. Hario's published 1,000 mL from 1,150 mL of water implies about 1.9, and Filtron's implies about 2.1. OXO's implies 1.3 to 1.7, so with OXO you may get more concentrate than the calculator says. Grind, roast and how long you let it drain all move this number, and we haven't measured it.

Cost is the coffee only, from the bag price and weight you enter. Nothing is looked up. For the makers themselves, see the best cold brew makers or the spec database.