Cold Brew Coffee Ratio Concentrate, Ready-to-Drink and Everything Between
Cold brew is not iced coffee. The process is different, the steep time is different and the math is completely different. Hot coffee brews at around 1:15 or 1:16. Cold brew concentrate starts at 1:4 or 1:5, which is three times stronger. That gap is what confuses most people and leads to batches that taste like muddy water or weak tea. Once you understand the two ratios and when to use each, the whole thing becomes simple. Here is what I use and why. For the general ratio math that applies to all brewing, see my coffee to water ratio guide.
Why Cold Brew Uses a Different Ratio
Cold water extracts coffee slowly. Very slowly. Hot water at around 200 degrees Fahrenheit pulls flavor from coffee grounds in 3 to 5 minutes. Cold water in the refrigerator takes 12 to 24 hours to do the same job.
To get enough extraction in that time, you need far more coffee relative to water than any hot brew method requires. The result is a concentrate you dilute before drinking.
The other benefit is what cold water does not extract. The bitter compounds and acids that dissolve quickly in hot water extract much more slowly in cold. Cold brew ends up smoother and less acidic than hot coffee even though the concentrate is far stronger. That is the whole appeal, and the ratio is what makes it work.
The Two Ratios You Need
Cold Brew Concentrate (1:4 to 1:5)
Use this for most home brewing. One part coffee to four or five parts water by weight. The result is a strong concentrate you dilute before drinking.
At 1:4 the concentrate is very strong. Good for people who want maximum flexibility when diluting or who prefer small, intense servings over ice.
At 1:5 you get a bit more liquid from the same amount of grounds and the dilution math is easier to dial in. This is my default starting point for most batches.
A 1:5 batch with 500 grams of water uses 100 grams of coffee, which is roughly 20 tablespoons. It sounds like a lot. It is a lot. That is cold brew.
Ready-to-Drink Cold Brew (1:7 to 1:8)
Use this if you want to pour and drink without any further diluting. One part coffee to seven or eight parts water. The result is weaker than concentrate but still stronger than a typical hot drip coffee.
This is close to what most store bought cold brew cans are. If you own a dedicated cold brew maker with a built in filter, this is often the ratio printed on the side of the box.
Cold Brew Coffee Ratio Chart
| Ratio | Per 500ml batch | Per 1 liter batch | How to use it |
|---|---|---|---|
| 1:4 (strong concentrate) | 125g coffee | 250g coffee | Dilute heavily before drinking |
| 1:5 (standard concentrate) | 100g coffee | 200g coffee | Dilute 1:1 with water or milk |
| 1:7 (ready to drink) | 71g coffee | 143g coffee | Drink straight from the fridge |
| 1:8 (lighter ready to drink) | 63g coffee | 125g coffee | Drink straight, mild strength |
The ratio stays constant no matter the batch size. If you scale down to a 250 gram water batch, just cut all the coffee amounts in half. Keep the ratio and the cup takes care of itself.
Cold Brew Dilution Calculator
Cold Brew Dilution Calculator
Choose your glass size and how strong you want it.
Based on a 1:5 home brew concentrate. Adjust to taste.
How to Make Cold Brew at Home
What You Need
Coarsely ground coffee, cold or room temperature water and a container large enough for both. A mason jar works. So does a French press (see my french press coffee ratio guide for the full setup). A dedicated cold brew maker has a built in filter that makes straining much easier. Cheesecloth or a paper coffee filter also do the job.
The Process Step by Step
Measure your coffee and water at your chosen ratio. Combine them in the container and stir gently to wet all the grounds. Cover and let it steep. In the refrigerator, expect 18 to 24 hours. At room temperature, 12 to 18 hours is enough.
When the time is done, strain slowly. Do not press or squeeze the grounds. Pressing pushes bitter compounds through into the finished brew. Let gravity do the work. Store the strained concentrate in a sealed jar in the refrigerator. It keeps well for about two weeks.
Steep Time and Temperature
Temperature affects speed and flavor. Cold (refrigerator at around 38 degrees Fahrenheit) means slower extraction and a smoother, cleaner result. Room temperature (around 70 degrees Fahrenheit) means faster extraction but sometimes a slightly more acidic or vegetal note.
I use the refrigerator method. The extra hours are worth it and cold brewing in the fridge also removes the small risk of over fermentation that can happen with a warm batch left out too long.
Twelve hours is a minimum. Twenty hours is my sweet spot for refrigerator cold brew at 1:5. Past 24 hours and most brews start tasting over extracted and flat.
How to Adjust Your Batch
Taste first. Then change one thing.
Weak or thin: steep a few more hours before pulling the grounds. If still weak at 24 hours, tighten the ratio toward 1:4 on the next batch.
Bitter or harsh: the grind is too fine or the steep ran too long. Go coarser next time and pull a few hours earlier.
Sour or sharp: under extraction, almost always from too little steep time. Steep longer or try room temperature on the next batch.
Muddy texture: the grind was too fine and particles got through the strainer. Use coarser grounds and strain twice through a coffee filter if needed.
Cold Brew Coffee Ratio FAQ
Quick answers from batches I have made at home.
For concentrate, use 1:5. For ready to drink, use 1:7 or 1:8. I always make concentrate at 1:5 and dilute to taste because it gives more control over every single glass.
Start with equal parts. One part concentrate to one part water or milk gives a strong, smooth cup. Go to one part concentrate and two parts water for something lighter. The calculator on this page shows the exact ounces for your glass size.
No. A 1:15 or 1:16 ratio brewed cold produces a thin, watery result even after 24 hours. Cold water needs far more coffee to extract properly. Use at least 1:8 for ready to drink and 1:5 for concentrate.
Three common causes: the grind was too coarse and left flavor locked in the grounds, the ratio was too loose to begin with, or 12 hours was not quite enough at refrigerator temperature. Steep to 18 or 20 hours, check the ratio and go coarser only if you are getting bitterness, not weakness.
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