Cold Brew Ratio Calculator: Coffee to Water

1:4 to 1:5 is the standard range for a concentrate you'll dilute before drinking — 1:4 makes a stronger concentrate, 1:5 (the classic Toddy-style ratio) is a bit more forgiving to dilute.

If you want to drink it straight over ice with no dilution, brew at a lighter 1:8 instead.

12 to 24 hours, depending on grind size, water temperature, and how strong you want the result.

Room temperature extracts faster than a refrigerator, so 12-16 hours at room temperature is roughly equivalent to 18-24 hours in the fridge.

Start tasting around the low end and extend if it's still weak.

Cold water extracts fewer of the acidic and bitter compounds that heat pulls out quickly, while still extracting sweetness and body over the long steep time.

That's a property of temperature and time, not the ratio — using more or less coffee changes strength, not acidity level.

Yes, similar to French press — a coarse, uniform grind is important.

A finer grind increases surface area and can over-extract during a 12-24 hour steep, plus it makes the concentrate harder to filter cleanly afterward.

A US quart is about 946 ml.

At a 1:8 ready-to-drink ratio that's roughly 118 g of coffee, and at a 1:5 concentrate about 189 g.

Enter your batch size above for exact amounts.

Concentrate is commonly kept refrigerated for up to about two weeks, and diluted ready-to-drink for a shorter time.

Store it sealed and cold, and discard it if it smells or tastes off.

Verify with your own sensory check rather than a fixed date.