12 Hour Cold Brew TimerFree 12 hour cold brew coffee timer. Cold brew needs 12–24 hours at room temperature or in the fridge. Set the timer before bed and wake up to perfect cold brew.Frequently asked questionsHow long should cold brew steep and why 12 hours specifically?12 hours at room temperature produces a well-balanced concentrate. Under 8 hours: under-extracted, weak, and sour. Over 24 hours at room temperature: over-extracted, bitter. In the fridge: 18–24 hours is optimal because cold slows extraction. 12 hours at room temp = 18+ hours in the fridge in terms of extraction.What ratio of coffee to water should I use for 12-hour cold brew?For concentrate (to dilute): 1:4 to 1:5 (1 cup coffee : 4–5 cups water). Drink directly: 1:8. Most commercial cold brew is made as a concentrate. A 12-ounce jar with 2oz coffee + 16oz water produces a good concentrate. Adjust based on how strong you prefer it.Does cold brew have more caffeine than regular hot coffee?Cold brew concentrate has significantly more caffeine than regular coffee (2–4x higher per ounce) because it's a concentrate. When diluted to drinking strength (1:1 with water or milk), caffeine per cup is similar to drip coffee (100–200mg per 12oz serving). Concentrate strength: use sparingly.What coffee grind is best for the 12-hour cold brew timer?Extra coarse grind (coarser than French press) is optimal. Fine grinds over-extract in 12+ hours and create sediment that's hard to filter. Extra coarse gives a cleaner concentrate with less bitterness. If you only have medium grind, reduce to 8–10 hours to prevent over-extraction.Can I cold brew at room temperature or does it need to be in the fridge?Both work: Room temperature (65–70°F): 12–14 hours, faster extraction, can be slightly more complex. Refrigerator (38°F): 18–24 hours, slower extraction, cleaner and less acidic result. Room temperature cold brew has more risk of bacterial growth if you go past 24 hours. Fridge is safer for longer steeps.