Immersion brewer
Filtron Cold Brew System: ratio and recipe
199g coffee1,893mL water
That is an everyday batch at 1:9.5, steeped 18–22 hours in the fridge and poured straight over ice. Holds 1,893 mL of water and takes up to 454 g of coffee.
The maker’s own recipe
1:4.2451 g coffee1,893 mL watersteep 12–24 h
This is the recipe Filtron publishes for this brewer, and it is what Cold Brew Studio opens with when you pick it. It makes about 8½ cups, best mixed 1:1 with water or milk.
How the maker does it
Filtron's own instructions (filtron.com): saturate the reusable felt filter pad in cold water, press it into the recess of the coffee bowl (domed up in the center, tab up), insert the rubber stopper from underneath, then pour 1 lb of regular-to-coarse ground coffee into the coffee bowl and level it with the grounds guard on top. Place the water bowl on top and fill it to its marked water line (the household unit's water bowl is commonly specified elsewhere, e.g. by resellers/roasters, as holding 48-56 oz — Filtron's own page doesn't restate the number, just 'the appropriate water line'). Let stand 12-24 hours (Filtron: 'minimum of 12 hours'; some roaster guides recommend ~16-20h). To drain, set the water bowl aside, lift the coffee bowl over the decanter, and pull the stopper — draining takes 30-60 minutes through the felt pad. Filtron notes concentrate is very strong: use at least 1 oz of concentrate per 6 oz of hot or cold water, and it suggests you can re-stopper the used grounds and repeat with half the water for a second, more economical batch. Concentrate keeps 4-6 weeks refrigerated.
Source: filtron.com
The recipe, by strength
Each one fills this brewer as far as it honestly goes. Numbers are for a light roast steeping in the fridge.
| Strength | Ratio | Coffee | Water | Steep | Makes | Drink it |
|---|---|---|---|---|---|---|
| Everyday | 1:9.5 | 199 g | 1,893 mL | 18–22 h | about 6¼ cups | straight over ice |
| Strong | 1:7.5 | 252 g | 1,893 mL | 18–22 h | about 5¾ cups | with a splash of milk |
| Jet fuel | 1:5.3 | 357 g | 1,893 mL | 18–22 h | about 7½ cups | cut with a little water or milk |
| Concentrate | 1:4.5 | 421 g | 1,893 mL | 18–22 h | about 9 cups | mixed 1:1 with water or milk |
If your beans are darker
Darker roasts give up their flavor faster, so they brew at a slightly wider ratio and steep for less time.
| Roast | Ratio | Coffee | Water | Steep in the fridge |
|---|---|---|---|---|
| Light | 1:9.5 | 199 g | 1,893 mL | 18–22 h |
| Medium | 1:10 | 189 g | 1,893 mL | 14–18 h |
| Dark | 1:10.5 | 180 g | 1,893 mL | 10–14 h |
Everyday strength shown.
How it goes
- Plug in, grounds in.
- Water over, slowly.
- Don’t stir.
- Lid on, into the fridge.
Grind coarse, about the size of coarse sea salt. Find the number for your grinder.
Good to know
The felt filter pad (Filtron's own, similar in concept to a Toddy) does the filtering, which is why the official grind guidance is only 'regular to coarse' rather than the extra-coarse grind mesh-strainer devices require to avoid sediment. It's also an immersion-then-gravity-drain design: after the steep, you pull a stopper and let the concentrate drain through the felt over 30-60 minutes rather than lifting out a basket or plunging — closer in mechanism to a Toddy than to a French-press-style cold brewer.
Let the app keep track.
Cold Brew Studio sizes every batch to your Filtron Cold Brew System, tells you when it is ready, and adjusts the recipe when you rate how it tasted.
Free on iPhone and the web. No account needed.
Quick answers
- How much coffee do I use in the Filtron Cold Brew System?
- For an everyday strength, 199 g of coffee to 1,893 mL of water, a 1:9.5 ratio. For a concentrate, 421 g to 1,893 mL.
- How long do I steep cold brew in the Filtron Cold Brew System?
- 18–22 hours in the fridge for a light roast, 14–18 for medium and 10–14 for dark. On the counter, 12–14, 9–12 and 7–9 hours.
- What ratio does the maker recommend for the Filtron Cold Brew System?
- 1:4.2, which is 451 g of coffee to 1,893 mL of water, steeped 12–24 hours.