Cold Brew Coffee FAQs

New to cold brew or trying to dial in your process? These are the most common questions about making, storing, and getting the most out of cold brew at home. If you want to nail your coffee-to-water ratio, use our free cold brew ratio calculator to build your exact recipe.

1. 1 How do you make cold brew?
   Cold brew is made by steeping coarsely ground coffee in cold or room-temperature water for 12–24 hours. Mix the grounds and water at roughly a 1:5 coffee-to-water ratio, let it sit, then strain out the grounds. The result is a smooth, low-acid concentrate you dilute before drinking. For a full walkthrough, see our guide on how to make cold brew coffee.
2. 2 How long does cold brew last?
   Cold brew concentrate stored in the refrigerator is best within 7–10 days, and can last up to two weeks if kept tightly sealed. Once diluted with water or milk, consume within a few days. If it smells or tastes off, discard it.
3. 3 Does cold brew have more caffeine than regular coffee?
   Cold brew concentrate has a higher caffeine concentration per ounce because of the higher coffee-to-water ratio used during brewing. However, since cold brew is diluted before drinking, a typical serving ends up with a similar or slightly higher caffeine level than a regular cup of coffee. The exact amount depends on your ratio and how much you dilute it.
4. 4 What kind of coffee should I use for cold brew?
   Medium to dark roast coffees work well because their bold flavors hold up during the long steep. That said, lighter roasts and single-origin beans can produce interesting results too — it’s worth experimenting. For best results, use freshly roasted whole beans and grind them coarsely just before brewing.
5. 5 What grind size should I use for cold brew?
   A coarse grind works best — roughly the texture of kosher salt or large sugar crystals, similar to a French press grind. A coarse grind slows extraction to match the long steep time, helps prevent over-extraction and bitterness, and makes filtering significantly easier.
6. 6 Should I use filtered water when making cold brew?
   Yes. Since coffee is mostly water, water quality has a real impact on flavor. Filtered or bottled spring water removes impurities that can dull or distort the taste. Tap water works in a pinch, but filtered water consistently produces a cleaner result.
7. 7 Can I use decaf beans to make cold brew?
   Yes. Decaf beans work just as well for cold brew. The process is identical, and you’ll get the same smooth, low-acid flavor profile without the caffeine — a good option if you want to enjoy cold brew in the afternoon or evening.
8. 8 Does cold brew have less acid than regular coffee?
   Cold brew is generally lower in acidity than hot-brewed coffee. Cold water extracts different compounds than hot water, producing a smoother, less sharp flavor. Many people who find regular coffee hard on their stomach tolerate cold brew better, though individual sensitivity varies.
9. 9 What can I make with cold brew concentrate?
   Cold brew concentrate is versatile. Dilute it 1:1 with cold water for classic cold brew, use it as a base for iced lattes, blend into frappes, mix into coffee cocktails, or dilute with hot water for a smooth, less acidic hot coffee.
10. 10 What is the ideal coffee-to-water ratio for cold brew?
    For concentrate, a 1:4 to 1:8 ratio (coffee to water by weight) is a common starting range. For ready-to-drink cold brew, ratios of 1:12 to 1:15 are typical. The best ratio depends on your preference — starting at 1:5 for concentrate is a reliable place to begin, then adjust stronger or weaker from there. Use the cold brew ratio calculator to dial in your exact amounts.