How to Make Good Cold Brew Without Using a Scale

We all know that measuring is the key to good results but hey, who’s got time for that? So how can you quickly throw together your cold brew without a scale? I did some digging and here’s what you want to know.

To make cold brew concentrate (1:4), use 1 cup of grounds for every 1,3 cups of water. To make ready-to-drink cold brew (1:9), use 1 cup of grounds for every 3 cups of water. Water is about 3,125 times heavier than grounds per volume. A 100 ml water cup can hold about 30-35 grams of coffee. 

Want to know which ratio you should use and how to fix your cold brew if you get it wrong? That’s what I’ll get into below.

---

How to Make Good Cold Brew Coffee Without Using a Scale

For brewing cold brew, you need to follow a ratio. A ratio for cold brew will look like this: ‘1:6’. This means 1 gram of grounds for every 6 grams of water. This means it’s a weight ratio, not volume. 

There are different ratios for different purposes. Ratios from 1:3 to 1:10 are possible for cold brew. The lower the second number of the ratio, the stronger the coffee will be. 1:3 to 1:5 are generally used for making concentrate which has to be diluted before drinking. 1:5 to 1:8 are good for serving over ice while 1:8 to 1:10 works well for drinking undiluted. Of course, personal tastes differ so some experimenting might be necessary. 

Using a scale is a good idea since you can get exactly the amount of grounds and water to get the exact ratio you want. However, cold brew is quite forgiving. And you can get away with not exactly getting the amounts right to the gram. 

The easiest way to make cold brew without a scale is to use cups, preferably measuring cups. Water weighs about 3.125 times as much as coffee grounds per volume. So a cup that holds 100 ml of water could hold about 30-33 grams of coffee grounds.

The 3,125 is an estimation and can differ a little since the grind size, type of beans, roast level, etc all have an impact on how heavy the grounds are per given volume. 

That means if you use 1 cup of grounds for one cup of coffee, you get to a roughly 1:3,125 ratio. This is very strong. Most people make cold brew concentrate with a 1:4 ratio. From here it’s pretty easy to figure out how to get there. 

Divide the second number of the ratio by 3,125 and you will have the number of cups of water you need to add to get that ratio. Sounds complicated? Below is a chart that shows you exactly how many cups you need. 

Cold Brew Cups Chart

Here’s a chart of how many cups of water to add to a certain number of cups of grounds. As long as you use the same cup for the grounds as for the water, this will work. Using a measuring cup is useful. Also, make sure the container is large enough.

Cups of Grounds	Cups of Water for 1:4 Ratio	Cups of Water for 1:6 Ratio	Cups of Water for 1:8 Ratio	Cups of Water for 1:10 Ratio
1	1,3	1,9	2,6	3,2
2	2,6	3,8	5,1	6,4
3	3,8	5,8	7,7	9,6
4	5,1	7,7	10,2	12,8

This chart tells you how many cups of water to add to a certain number of cups of grounds to get to the listed ratio. The cups are rounded to one decimal point since you likely won’t be able to measure more precisely than that. You can see a measuring cup is very useful for getting the right amounts. 

Make sure to use a dry cup to put the grounds into the container otherwise a lot of the grounds will get stuck to the cup. 

Some things to remember

• Make sure your container is big enough to contain all the liquid and coffee grounds before you start.
• Measure out the coffee grounds first. This way the cup isn’t wet because you measured the water first.
• Coffee grounds soak up water. Every gram of coffee grounds holds onto about 2 grams of water. That means adding 6 cups of water will yield fewer cups in the end. However, cold brew is usually diluted or served over ice which means you get about the same in the end. 
• Make enough to have enough for a few days so you don’t have to make a batch every day. But also don’t make so much you can’t finish it within a week. After 4 or 5 days the taste will start degrading.

What Happens If You Use The Wrong Ratio?

What happens if you get it wrong and you end up with the wrong ratio of coffee to water? Don’t worry, it’s not a big deal and pretty easy to fix.

Too much coffee

Using too much coffee for the amount of water is pretty difficult in cold brew. That’s because it’s pretty difficult to get too much coffee grounds in cold brew in the first place. Some people make cold brew concentrate with a ratio as low as 1:3.

That’s a lot of coffee for the amount of water and it’s actually pretty hard to get there by accident, especially if you’re shooting for 1:6 or similar.

But let’s say you drop a bag of coffee grounds in your cold brew container. Well, what happens is that you just end up with cold brew concentrate.  And that’s easy to solve. Just add water and/or ice. Cold brew is pretty much always diluted even in higher ratios. So adding some extra to get it to your preferred taste is not a big deal.

If you think the taste is too strong, you can also try adding some of the popular add-in tastes. Cold brew is often mixed with other things than water and ice which changes the taste.

My cold brew is too weak!

If your cold brew is too strong, the solution is very simple. Just add more water or ice. That will fix that problem really easily.

But what about when it’s too weak? Well, don’t be so stingy with the coffee but that’s for next time. What can you do now?

Should you keep cold brew in the fridge?

You can’t just take water away, right? Well, technically you could through evaporation. There are some problems with evaporation though. Just drinking it undiluted and not over ice will probably mean it’s strong enough. 

If it’s still not strong enough undiluted, you can make a stronger batch of cold brew and mix it with the weaker batch. 

You could also turn the stronger batch into ice cubes. Then add those cubes to the weaker batch. This way the cold brew doesn’t dilute when the ice melts but actually gets stronger. 

By the way: It’s much better to brew and especially store cold brew in a glass container. Here’s an article explaining why.