The 7 Reasons Why Your Coffee Machine Is Making Weak Coffee

Last Updated on May 13, 2022 by John Moretti

Everyone likes their coffee differently, but no one enjoys weak coffee. If you are a coffee person, it is likely that you have invested a lot of time and effort into getting your own home coffee set up functioning, and if your coffee machine of choice is brewing weak coffee, this can be a frustration. Let’s learn why a coffee machine may make weak coffee and how to solve the issue.

Your coffee machine may be making weak coffee due to insufficient coffee for the brew size, too much water for the amount of coffee, a short brew time, low water temperature, incorrect coffee grind size, a change in coffee roast level, or a faulty coffee machine. 

If your coffee machine is producing weak coffee, there are several reasons that may be to blame. The best way to solve this complicated issue is to work through the list of possible causes until you find the one that has befouled your coffee machine and take action to rectify the issue. The root causes of these problems are usually simple to rectify.

Photo of weak coffee in clear glass

The 7 Reasons Why Your Coffee Machine Makes Weak Coffee

If your home coffee machine is suddenly brewing weak coffee, if you have purchased a new machine that brews coffee weaker than you may like, or if you are trying to find a way to brew stronger coffee with your coffee machine, there are several options that can be explored in order to produce a stronger brew. 

Brewing coffee is surprisingly complicated, and there are several factors that contribute to the success of a brew and the strength of the coffee liquid. To coax stronger coffee from a coffee maker, certain criteria must be met in order for the brew to happen successfully. 

Let’s explore the reasons why your coffee maker may be producing weak coffee brews and how to produce stronger coffee with any coffee maker. 

1. Not Enough Coffee in The Brew Ratio

Image of grind coffee placed on filter

The most common reason for a weak coffee brew is an incorrect brew ratio. The most important aspect of the ratio and the ultimate deciding factor in the strength of a brew is how much coffee is used in the brew. 

If you are using an insufficient amount of ground coffee for the amount of water used to brew, the resultant brew will be very weak and lackluster. 

The way to rectify this issue is to simply add more coffee to your brew. If your coffee tastes and looks stronger after adding more ground coffee, then this was the issue from the beginning. 

2. Too Much Water In The Brew Ratio

Photoo of three pitchers of water and  some ground coffee

The other aspect of the brew ratio in coffee is how much water is used for brewing. If there is not enough coffee for the brew, it can taste weak, but if there is too much water in the brew, this can produce a weak cup of coffee as well. 

If you are using an appropriate amount of ground coffee for your brew and it still turns out weak, you may be using too much water for the brew, or the machine may be set to use too much water for the brew depending on what type of machine you use for brewing coffee. 

If this is true for you, try adjusting the brew ratio to use less water or add less water to the machine. This will increase the strength and intensity of the brew. 

3. Short Brew Time

A very important yet often overlooked aspect of brewing coffee is brew time. If the water is not allowed enough time to extract the ground coffee beans, the resultant brew will be very weak. 

For this reason, it is vital for the brew to be sure that the water is in contact with the ground coffee for enough time to fully extract the coffee without over-extracting the beans. 

How long the brew time should be is dependent on how coffee is used in the brew ratio, but if your water and coffee ratios are correct, try letting the brew happen more slowly. This will increase coffee extraction and produce a stronger brew. 

4. Low Water Temperature

Coffee requires high brew temperatures or very long brew times to properly extract. In most instances, a very long brew time is not ideal, so a higher temperature is the way to brew more effectively. 

Coffee should be brewed at high temperatures for the best possible extraction. If your machine is brewing weak coffee, try using hotter water for the brew or setting the machine to use a higher brew temperature. 

5. Incorrect Coffee Grind Size

Another important factor in a successful brew is how fine or coarse the coffee beans are ground. If your coffee beans are ground too coarse, they will not fully extract in the brew, and this will lead to a weak cup of coffee. 

Try grinding the coffee beans finer to increase the extraction and brew time. This will increase the strength of the brew significantly. 

6. Roast Level Confusion

photo of four types of coffee roasts

The way certain coffee beans taste can sometimes be confused with tasting weak, but in reality, they have the same strength but a mild or lighter flavor. This is true with light roasted coffee

If you are used to dark roasted coffee beans and find yourself using light roasted beans, the beans will brew similarly but taste very different. Light roasted beans taste more acidic and lighter, which may make them feel weaker when the strength of the coffee is the same. 

However, lighter roasted coffee is more difficult to extract. Therefore, the temperature, grind size, and brew ratio must be adjusted accordingly for a strong brew with light roasted coffee. 

7. A Faulty Coffee Machine

At the end of it, if you have rectified these issues and your coffee machine is still producing weak coffee, then there is likely something wrong with the machine that is affecting the brewing process negatively. 

Send the machine for a service to rectify any issues, and the repaired machine should work well for brewing strong coffee. 


Brewing coffee is complicated, and brewing strong coffee is only possible if the correct chain of tractors is met accordingly. For this reason, it is important o understand what affects coffee brewing rather than simply wondering why the brew may be weaker than usual. 

Take the time to understand how coffee brews and what factors affect coffee extraction, and your coffee brew will never taste weak again!