Cold Brew Coffee: Easy Overnight Recipe and Ratio
Smooth, sweet, and low in acidity. Steep coarse grounds overnight for a concentrate you can keep all week.
Updated May 20, 2026
- Brew time
- 12–18 hrs
- Ratio
- 1:8 concentrate
- Grind
- Coarse
- Difficulty
- Beginner
Cold brew steeps coarse coffee in cool water for 12–18 hours. Because no heat is involved, it extracts fewer acids and bitter compounds than any hot-brew method — producing a naturally sweet, mellow concentrate with about 60–70% less acidity than drip coffee. One batch kept in the fridge gives you café-quality iced coffee for a full week.
What you need
- A large jar, pitcher, or dedicated cold brew maker (at least 1 liter)
- 100 g of coffee beans (medium-dark or dark roast works best)
- A burr grinder set to extra coarse — like cracked peppercorns
- 800 g of cold, filtered water
- A fine-mesh strainer and a paper coffee filter for straining
Step-by-step cold brew recipe
- 1Coarsely grind 100 g of coffee. The grind should be noticeably coarser than French press — almost chunky. Fine grounds over-extract during a long steep and turn bitter.
- 2Add the grounds to your jar and pour in 800 g of cold, filtered water. Stir well to ensure every ground is saturated.
- 3Cover with a lid or plastic wrap and place in the fridge. Steep for 12–18 hours. Taste at 12 hours — if it is too mild, steep to 15 or 18 hours.
- 4Strain through a fine-mesh sieve into a clean jar. For a crystal-clear result, strain a second time through a paper coffee filter.
- 5Cap and refrigerate your concentrate. It keeps for up to 2 weeks.
- 6To serve: pour 100–120 ml of concentrate over a glass of ice, then add an equal amount of water or milk. Adjust to taste.
Pro tip: Room-temperature steeping cuts the time to 8–12 hours and gives a slightly brighter, more acidic flavor. Refrigerator steeping is slower but more forgiving — you can leave it overnight without worrying about over-extracting.
Concentrate vs ready-to-drink
The recipe above makes a concentrate (1:8 ratio) that you dilute before drinking. If you prefer to pour straight over ice with no mixing, use a 1:15 ratio instead — 67 g of coffee to 1 liter of water, steeped for the same time. The ready-to-drink version is less concentrated and more delicate, but takes up more fridge space per serving.
Cold brew serving ideas
- Classic iced cold brew: 1 part concentrate, 1 part water or oat milk, over ice.
- Cold brew latte: 1 part concentrate, 2 parts milk (any kind), no ice needed if concentrate is cold.
- Cold brew tonic: 1 part concentrate, 2 parts tonic water over ice. Add a citrus slice.
- Frozen concentrate cubes: freeze concentrate in an ice tray and add to hot coffee or milk for an instant iced drink that never dilutes.
Frequently asked questions
What is the best ratio for cold brew concentrate?
Use 1:8 coffee to water by weight for a concentrate — for example 100 g coffee to 800 g water — then dilute 1:1 with water or milk when serving. For ready-to-drink cold brew, use 1:15 and skip the dilution step.
Is cold brew stronger than regular coffee?
The undiluted concentrate is much stronger. Once diluted to a 1:1 ratio, the caffeine per cup is similar to hot drip coffee — though cold brew often tastes smoother and sweeter, which can make it easy to drink more than you intend.
Why is my cold brew bitter?
Bitterness in cold brew usually means the steep was too long or the grind was too fine. Try a coarser grind first, and limit steep time to 18 hours maximum. Very fine grounds can over-extract even at cold temperatures over long periods.
How long does cold brew last in the fridge?
Properly stored cold brew concentrate keeps for up to 2 weeks. Ready-to-drink (diluted) cold brew is best within 7 days. Always store sealed in the fridge — cold brew exposed to air stales quickly.