How to Make Cold Brew Coffee (Complete Guide + Ratio Calculator)

Cold brew coffee is smooth, naturally sweet, and surprisingly easy to make at home — once you know the right ratio. This guide walks you through the whole process, from coffee-to-water measurements to steep time to storage, so you get a great batch every time.

The most important variable in cold brew is your coffee-to-water ratio. Get that right, and everything else falls into place. Use our free Cold Brew Ratio Calculator to find the exact measurements for any batch size before you start.

What Is Cold Brew Coffee?

Cold brew is coffee made by steeping coarsely ground beans in cold or room-temperature water for an extended period — typically 12 to 24 hours. Unlike iced coffee (which is hot-brewed coffee cooled down and poured over ice), cold brew is never exposed to heat during the brewing process.

The result is typically smoother and noticeably less harsh than regular coffee. Cold water extracts compounds from coffee more slowly and selectively than hot water, pulling out many of the rich, sweet, chocolatey flavors while leaving behind some of the sharper acids and bitter compounds that hot brewing rapidly extracts in minutes. This slower extraction is what gives cold brew its characteristic smooth, mellow character.

Cold brew is also generally perceived as less acidic-tasting than hot coffee, though it’s worth noting this is largely a flavor perception — the actual pH difference varies depending on your brewing method and ratios. What most people notice is that it’s easier on the stomach and requires less (or no) added sweetener.

Key benefits of cold brew:

• Smoother, less harsh taste compared to hot-brewed coffee
• Generally perceived as lower in acidity — easier on the stomach for many people
• Higher caffeine concentration when brewed as a concentrate
• Stays fresh for up to two weeks in the fridge when stored properly
• Versatile — serve over ice, diluted with hot water, or as a base for lattes and cocktails

What You Need to Make Cold Brew at Home

Cold brew requires minimal equipment. You likely already have most of this at home.

Equipment

• Large jar or pitcher — A 64 oz wide-mouth mason jar works well and is inexpensive
• Fine-mesh strainer or coffee filter — For filtering out the grounds after steeping
• Stirring spoon
• Refrigerator or cool, dark space for steeping

Optional: A dedicated cold brew maker, French press, or a pressure-based system like JARVA can speed up filtration dramatically — filtering a full batch in under 60 seconds instead of the 20-40 minutes gravity filtration typically takes.

Ingredients

• Coarsely ground coffee — Medium-to-coarse grind is important (more on this below)
• Cold or room-temperature water — Filtered water tends to produce the cleanest flavor

That’s it. No special ingredients, no expensive gear required.

The Cold Brew Coffee-to-Water Ratio

Your ratio determines how strong your cold brew is — and whether you’re making a concentrate to dilute later or a ready-to-drink brew. Getting this right matters more than almost anything else in the process.

A quick note on measurements: the ratios in this article are expressed as grams of coffee to milliliters of water (e.g., 1:5 means 1g coffee per 5ml water). Since water has a density of approximately 1g/ml, this is effectively the same as a weight-to-weight ratio, which is how many coffee enthusiasts measure. Either approach works fine.

Ratio	Type	Flavor Profile	Best For
1:2 (1g coffee : 2ml water)	Super Concentrate	Very intense, syrupy	Coffee cocktails, lattes
1:4 (1g coffee : 4ml water)	Concentrate	Rich, bold	Dilute 1:1 before drinking
1:5 (1g coffee : 5ml water)	Standard	Balanced, smooth	Best starting point for most people
1:6 (1g coffee : 6ml water)	Light	Mild, delicate	Sensitive stomachs, lighter preference
1:8 (1g coffee : 8ml water)	Very Light	Subtle	Very mild cup — most people find this too weak

The most popular starting point is 1:4 or 1:5. If you’re making a concentrate (the most common approach), use 1:4 and dilute with an equal part water or milk when serving. If you want something ready-to-drink straight over ice, go with 1:5 or 1:6.

Quick Cold Brew Ratio Reference

Here are approximate starting measurements for common batch sizes at a 1:5 ratio. Keep in mind that coffee grounds absorb water during steeping (roughly 2ml per gram), so your finished yield will be somewhat less than your total water volume. The calculator below will give you exact numbers for any batch size and ratio.

Jar / Container Size	Coffee (1:5)	Water (1:5)	Approx. Finished Yield
32 oz jar	~85g (3 oz)	~425ml (~14 oz)	~10–12 oz concentrate
64 oz jar	~170g (6 oz)	~850ml (~29 oz)	~20–24 oz concentrate
1 gallon jar	~340g (12 oz)	~1,700ml (~57 oz)	~40–48 oz concentrate

Note: these examples fill roughly half to two-thirds of each jar, leaving room for grounds and allowing easy stirring. You can scale up to use more of your container’s capacity — use the calculator to dial in your preferred amounts.

How to Make Cold Brew Coffee: Step-by-Step

Follow these steps for a clean, smooth batch every time.

Step 1: Grind Your Coffee Coarse

Use a medium-coarse to coarse grind — similar in texture to raw sugar or coarse sea salt. This is the single most important variable after your ratio.

Finer grounds have more surface area, which causes them to extract more aggressively during the long cold steep. This typically results in a muddy, over-extracted brew with noticeable bitterness and more sediment in the finished cup. Fine particles also pass through filters more easily, leaving your cold brew gritty and less clear. Coarse grounds extract more slowly and evenly, producing the clean, smooth character cold brew is known for.

If you’re buying pre-ground coffee, look for bags labeled “cold brew grind,” or ask your local roaster to grind coarse. Most grocery store pre-ground coffee is on the finer side — it can work in a pinch if you reduce the steep time slightly, but freshly coarse-ground beans will consistently produce better results.

Step 2: Measure Your Coffee and Water

Use the Cold Brew Ratio Calculator to get your exact measurements. For reference, brewing in a 64 oz mason jar at a 1:5 ratio typically looks something like 170g of coffee and around 850ml (about 29 oz) of water — filling roughly half the jar before accounting for the grounds. That’s intentional: coffee grounds take up volume, absorb some water, and you’ll want room to stir without making a mess.

Your actual usable water volume will vary based on your grind size, jar shape, and how much headroom you prefer to leave. This is why the calculator is useful — plug in your jar size and preferred ratio, and it gives you the right numbers without the guesswork.

Weighing your coffee on a kitchen scale gives you much more consistent results than using volume measurements. A tablespoon of coarsely ground coffee can vary quite a bit in weight depending on how it’s scooped.

Step 3: Combine Coffee and Water

Add the coffee grounds to your jar or pitcher first, then pour the cold or room-temperature water over them. Stir gently for 30-60 seconds to make sure all the grounds are fully saturated — dry clumps sitting on top will under-extract and produce an uneven brew.

Traditional cold brew uses cold or room-temperature water throughout. Adding hot or even warm water changes the extraction profile significantly, producing a different flavor character — faster extraction, more acidity, and a less smooth result. Some experimental methods do incorporate hot water intentionally (such as flash-chilled cold brew), but for a standard cold brew, stick with cold or room temp.

Step 4: Steep for 12 to 24 Hours

Cover your container and let the coffee steep. The two main approaches:

Method	Location	Steep Time	Notes
Cold Steep	Refrigerator	18–24 hours	Cleanest flavor, safest, most common
Room Temp Steep	Countertop	12–16 hours	Slightly faster, bolder flavor — filter promptly when done

Steeping in the fridge is the go-to method for most home brewers. The cold temperature slows extraction, giving you more control and a cleaner cup. Room-temperature steeping moves a bit faster but needs closer attention — leaving it too long at room temp can start producing off-flavors.

For most recipes, around 18–24 hours is a practical upper limit when cold steeping. Longer steep times tend to increase bitterness and extraction of less desirable compounds, so it’s generally worth filtering when you hit that window. That said, some people do steep longer intentionally for a stronger, more intense flavor — just expect a different (and sometimes harsher) result.

Step 5: Filter Out the Grounds

Once steeping is complete, filter the coffee from the grounds. If you’re using gravity, this step takes some patience — a standard mesh strainer with a paper coffee filter can take 20-40 minutes to drain a large batch.

Filtering options:

• Fine mesh strainer + paper filter — Slowest, but produces the cleanest, clearest brew
• Cheesecloth — Faster but less thorough; may leave some sediment
• French press plunger — Quick and easy, though some fine particles may pass through
• Dedicated cold brew maker — Built-in filters, easier cleanup
• Pressure-based system (e.g., JARVA) — Uses air pressure instead of gravity to push coffee through multi-layer filters, cutting filtration time to under 60 seconds

Whatever method you use, try to avoid pressing or squeezing the grounds forcefully — this can push bitter compounds into the finished brew.

Step 6: Store and Serve

Transfer the filtered cold brew into a sealed glass jar or pitcher and store in the refrigerator.

• Best flavor window: Within 7–10 days for both concentrate and ready-to-drink cold brew
• Maximum shelf life: Concentrate can often remain drinkable for up to 2 weeks if kept sealed and properly refrigerated, though flavor quality gradually declines after the first week
• To serve: If you brewed a concentrate (1:4 ratio), dilute with an equal part cold water, milk, or oat milk before drinking
• Over ice: Pour concentrate over ice and add your diluent of choice
• Hot cold brew: Dilute concentrate with hot water for a smooth, gentle hot coffee — counterintuitive but genuinely good

Tips for Better Cold Brew Coffee

Use Freshly Ground Coffee

Pre-ground coffee starts losing its aromatic compounds soon after opening. If possible, grind whole beans right before brewing. For a 20-hour steep, freshness genuinely makes a difference in the final cup.

Choose the Right Roast

Cold brew works with any roast, but medium and medium-dark roasts tend to produce the most balanced, chocolatey results. Light roasts produce a brighter, more complex cup. Very dark roasts can taste heavy or almost syrupy. A medium roast is a reliable starting point if you’re unsure.

Use Filtered Water

Water makes up the vast majority of your cold brew. If your tap water has a noticeable taste or heavy chlorine, it will show up in the final cup. Filtered water — even a simple Brita pitcher — typically makes a meaningful difference.

Scale Your Recipe Precisely

The difference between a 1:4 and 1:5 ratio may sound minor, but it produces a noticeably different cup. Use the Cold Brew Ratio Calculator to get exact gram measurements for your batch size rather than eyeballing with cups or tablespoons.

Don’t Skip the Stir

Stirring at the start ensures all the grounds are fully saturated. Dry grounds sitting on top of your jar will under-extract, creating an uneven brew. A 30-second stir at the beginning costs almost nothing and consistently improves the result.

Label Your Jar

Write the brew date and ratio on a piece of tape on the jar. After a few days in the fridge, it’s easy to lose track of when you brewed it and how concentrated it is. A quick label saves confusion and wasted coffee.

How to Make Cold Brew Concentrate

Cold brew concentrate is cold brew made at a stronger coffee-to-water ratio — typically 1:4 or higher — and then diluted before drinking. It’s the most popular home cold brew approach because:

• You use less total water during brewing, so a smaller container works fine
• The concentrate stores more efficiently (takes up less fridge space)
• You control the strength of each serving by adjusting how much you dilute
• It works as a versatile base for lattes, iced drinks, and coffee cocktails

To make concentrate, use a 1:4 ratio (1 gram of coffee per 4ml of water). After steeping and filtering, dilute roughly 1:1 with cold water or milk when serving. Adjust to your taste from there — some people prefer a 1:2 dilution for a stronger cup, others go a little lighter.

Use the calculator to find the exact amounts for any concentrate ratio and batch size.

Frequently Asked Questions

What is the best coffee-to-water ratio for cold brew?

The most popular starting points are 1:4 for concentrate (dilute before drinking) or 1:5 for a ready-to-drink brew. Both tend to produce a smooth, well-balanced cold brew for most people. Use the Cold Brew Ratio Calculator to get exact measurements for your batch size.

How long should I steep cold brew?

Typically 18–24 hours in the refrigerator, or 12–16 hours at room temperature. Cold steeping in the fridge gives you more control and a cleaner flavor. Steeping much beyond 24 hours can start producing bitterness for most recipes, though results vary depending on your ratio and grind size.

What grind size should I use for cold brew?

A medium-coarse to coarse grind — similar to raw sugar in texture — works best for most people. Finer grinds tend to over-extract during the long steep, producing bitterness and more sediment. They also make filtering much more difficult.

Can I use pre-ground coffee for cold brew?

Yes, though most store-bought pre-ground coffee is on the finer side. If using pre-ground, look for a product labeled “cold brew grind,” or try reducing your steep time slightly to compensate. Freshly ground whole beans at a coarse setting will generally produce better results.

How do I know if my cold brew is concentrate or ready-to-drink?

It comes down to your ratio. If you brewed at 1:4 or stronger, you have a concentrate — dilute it roughly 1:1 with water or milk before drinking. If you brewed at 1:5 or weaker, it’s typically ready to enjoy straight over ice. The Cold Brew Calculator indicates this based on the ratio you enter.

How long does cold brew last in the fridge?

Cold brew tastes best within the first 7–10 days when stored sealed in the refrigerator. Concentrate can often remain drinkable for up to 2 weeks if stored properly, though flavor quality gradually fades. Always keep it sealed — cold brew readily picks up fridge odors when left open.

Does cold brew have more caffeine than regular coffee?

Cold brew concentrate typically contains more caffeine per ounce than regular drip coffee, because of the higher coffee-to-water ratio used in brewing. Once you dilute the concentrate 1:1, caffeine content is roughly comparable to regular coffee. The exact amount depends on your ratio, steep time, and the coffee itself.

Can I make cold brew without special equipment?

Absolutely. All you need is a large jar, coarsely ground coffee, cold water, and a fine-mesh strainer or coffee filter. A French press works especially well — steep your grounds directly in the press, then plunge and pour. No special equipment required.

What is the difference between cold brew and iced coffee?

Iced coffee is hot-brewed coffee cooled down and poured over ice. Cold brew uses cold water throughout and is never heated. Cold brew tends to taste smoother and less sharp, while iced coffee is faster to make but can taste more bitter and dilutes quickly as the ice melts.

Ready to Brew?

Making cold brew at home is one of the most low-effort ways to upgrade your daily coffee. Once you dial in your ratio, the active prep time is under 10 minutes — and you’ll have a week’s worth of smooth, ready-to-go coffee waiting in your fridge.

The key steps:

1. Choose your ratio (1:4 for concentrate, 1:5 for ready-to-drink)
2. Grind coarse
3. Steep 18–24 hours in the fridge
4. Filter
5. Enjoy within 7–10 days for best flavor

Use the Cold Brew Ratio Calculator to scale any recipe to any batch size instantly — whether you’re making a single serving or a full gallon.