The right coffee filter can make or break your next cup of joe, and you should choose it correctly. This guide shares insights into everything you should know about the best coffee filter sizes, types, and shapes for you.
The market is flooded with plenty of filters made with materials such as paper, cloth, and metal. The shapes are conical, disk, and basket, depending and what you prefer.
If you are looking for a solution for terrible coffee, you may want to add to your cart the very best size, shape, and type of coffee filter for your coffee maker rather than the first available or cheapest coffee filter. I painfully realized that coffee filters aren’t just filters after a series of bad coffee; they are the key to a good cup of Joe as they improve the texture and the flavor of the coffee. Had I known this earlier, I’d have saved a lot, especially because finding proper coffee filter size, type, and shape is more challenging than I imagined. But after extensive research and countless mistakes, I came up with this guide for the best coffee filters. So, keep reading to learn more!
How do coffee filters work?
With coffee filters holding the doors to coffee heaven by ensuring the most flavorful, colored, tasty, and best coffee aroma, you should know that coffee filters work based on a simple scientific operation – separation of the grounds and coffee oils from your espresso.
The best coffee filters give you control over the brewing process’ degree of extraction by influencing how water percolates the coffee grounds. However, this is only possible if the shape of the coffee filter is right.
Other than the shape of the coffee filters, the material used to make the filter is equally important – it’s as essential as the coffee beans used.
The material is essential because it absorbs oils from the ground coffee, reducing the bitterness of the coffee. The material also affects the size of the filter’s pores. Filters with large pores allow more coffee grounds to pass through the filter, yielding more decadent flavors of coffee. In other words, the filters work by determining how water percolates the coffee and what is allowed to pass through, directly influencing the richness and flavors of your coffee.
Note that when it comes to electric coffee machines, a filter is also used. Still, these appliances’ brewing process starts with cold water that’s heated up during the brewing process, and the filters are considered permanent.
How many types of coffee filters are there?
Most of the coffee filters on the market today are paper filters. A paper filter is easy to use since you place it over the pot in a conical shape after measuring the right amount of ground coffee. Paper filters are also popular because of their high absorbance from tightly woven paper. The paper filters work well in trapping oils, among other particles, thanks to the tight weaving. They also create smoother brews with low acidity.
Paper filters are also great for individuals watching their cholesterol levels because these filters trap coffee oils too. The coffee oils fall in the lipids called diterpenes, which are known to raise blood LDL or bad cholesterol levels, liver enzymes, and triacylglycerols. A paper filter will filter the diterpenes if you are watching your numbers. And unfiltered coffee has at least 30 diterpenes (such as kahweol and cafestol)
Bleached vs. Unbleached paper coffee filters
Paper coffee filters are available in any grocery store, and the filters can be bleached or unbleached. The bleached paper filters aren’t white, thanks to the bleaching process on natural, off-white paper. Bleaching is necessary to increase the paper’s ability to trap some of the finest coffee particles and yield smoother or velvety-tasting coffee. The coffee filters are bleached using either chlorine or oxygen, but oxygen is an ideal bleaching agent because it’s much more eco-friendly, although this process isn’t 100% safe.
On the other hand, you have unbleached coffee filters. The paper isn’t overly processed, meaning it’s a much eco-friendlier solution. While unbleached coffee filters are affordable and readily available in grocery stores, these filters aren’t as effective, and they leave a papery taste in your coffee.
While it boasts clean, crisp, bright, and light coffee flavors and is convenient with minimal cleanup (the filter isn’t reusable), the paper filter has too much waste.
Cloth coffee filters are the market’s least common type of filter today. They are made of cloth fibers, tightly woven to trap even the tiniest ground coffee particles. Thanks to the woven design of the cloth coffee filters, your coffee will be sediment-free, with a nice, mid-level mouth feel that is both aromatic, acidic, and robust. Since the cloth fibers don’t trap coffee oils, I wouldn’t recommend them if you watch your cholesterol levels.
While cloth coffee filters give you the most delicious cup of coffee by trapping the unappealing elements and that they are the most eco-friendly solution, these filters are painfully difficult to clean – you’d have to empty the coffee grounds, wash the cloth, and then dry it.
Cloth filters offer a full coffee flavor profile that is medium-bodied, bright, clean, and aromatic. Cleanup is quick, and the filter has minimal waste.
The third type of common coffee filter is the metal coffee filter. The pores on the metal filters are intermedia, between the paper and the cloth filters. While the metal filters ensure a stronger, full-bodied cup of coffee, they won’t filter the coffee oils.
According to coffee aficionados, there shouldn’t be much Brouhaha around coffee oils because contrary to the belief that these oils contain diterpenes that increase bad cholesterol levels, the coffee oils are crucial for a boost in the aroma of the coffee. I agree with these claims because the natural coffee oils give coffee that desirable big mouthfeel alongside the boldness and richness of the coffee. So, if these elements are essential to you, as they are to me, then the metal filter would be an excellent option for you.
Metal filters are easily reusable but hard to clean and maintain. Dumping out the used ground coffee and washing the filter in warm water and a gentle soap/ detergent might work well, but some of the grounds may be stuck in the mesh.
If you want to use metal coffee filters, you should know that there are two main types of metal filters – mesh cones with single and double-layered designs and round, basket metal filters.
The mesh cone coffee filters are more common, and the single or double-layered designs work with or without stands. Therefore, I recommend this filter for use at home or when camping outdoors because it’s efficient, convenient, and eco-friendly. You can choose either design based on the design of your coffee pot.
Note that the metal filters are responsible for the high-perceived coffee acidity. But the trapped oils and the micro coffee grounds from past coffee brews will stick around the filter.
The metal filter is equally easy to clean; it boasts bold, heavy, rich, and aromatic flavor profiles and a relatively easy cleanup.
What are the shapes of a coffee filter?
Here are the common shapes of coffee filters to take note of:
The first type of coffee filter shape you’ll come across is the disk-shaped coffee filter. This filter is much smaller than the others you’ll read about here. As the name suggests, these coffee filters are flat and round, like disks. These filters are common in French presses and AeroPress coffee brewers.
You’ve probably used a French press before, and even if you haven’t, you know that this filter traps the used coffee grounds inside your coffee maker after a flood of water is mixed with the coffee in the carafe.
The basket coffee filter looks just like a cupcake liner, with its flat bottom rather than the conical, narrow end of the conical filters. With the basket shape, the coffee grounds are spread evenly across the surface of the filter. The basket coffee filters mean that your coffee grounds don’t enjoy equal access to the hot brewing water, so the coffee’s quality isn’t as good as that of the coffee steeped through the conical filter.
Now, you may think that uneven access to water means terrible coffee. Well, this isn’t the case. If anything, the basket-shaped coffee filters will slightly lower the strength of the coffee, resulting in sweet, floral coffee flavors with minimal umami and earthy notes. So, choose the basket-shaped filter if this sounds like your perfect cup of coffee.
The conical filters look like funnels or upside-down party hats. With the narrow bottom, these filters and the classic drip coffee makers are a match made in coffee heaven.
A conical-shaped coffee filter allows you to pour water over the filter. The water then percolates, and you get an excellent, even-bodied extraction with subtle aromas and flavors and the perfect-tasting coffee.
What are the coffee filter sizes?
Filter shapes and materials guide the quality of your coffee, but you should consider the size of the coffee filter too.
Ideally, coffee filter sizes range from 8 to 12, although you’d need a smaller, junior-sized basket coffee filter if your coffee machine uses a much smaller filter.
But this isn’t the only thing you should know about the sizes of the coffee filters; you also need to note that the sizes are variable for the cone filters in sizes #1, #2, #4, and #6. And these numbers correlate to the size of your coffee machine.
Here’s a breakdown of what the numbers represent.
- #1 is a filter for one-cup or single-serve coffee machines,
- #2 is the filter size recommended for coffee machines with 2-6 cups.
- #4 represents coffee filters for 8-12 cup coffee machines
- #6 coffee machine filters are ideal for larger-capacity coffee machines.
For clarity, the most common sizes of coffee machines and coffee filters are sizes #2 and #4.
How do you choose a good coffee filter?
A good coffee filter is the type of coffee filter that ensures your desired flavor, taste, body, and texture of coffee.
Based on considerations like the materials used and the shape of the coffee filters, you will end up with a bold or sweet coffee, with or without oil.
Other than the size, shape, and material used for the coffee filter’s construction, consider these other features:
The thickness of the coffee filter – the thickness of the filter is often ignored, but it plays an important role in the quality of your coffee. For the best quality, sediments-free, and strong coffee, the thicker the filter, the better. Avoid ultra-thin coffee filters because water percolates through them quickly, and the coffee won’t be extracted well. Unfortunately, the filters with the right thickness are much more expensive.
Bleached or unbleached – as mentioned above, oxygen-bleached coffee filters made of paper will keep all sediments out, ensuring the best quality and the strongest coffee brews. But they aren’t eco-friendly. Conversely, the unbleached coffee filters aren’t as effective in steeping coffee, but when wet before brewing, the unbleached coffee filters are more suitable, albeit at a higher price tag.
Coffee quality – depending on the coffee you like, there is a coffee filter you can use. A metal filter delivers bolder, richer, and cloudier coffee with little sedimentation and coffee oils for a full-bodied, fruitier, and sweeter coffee. Paper filters trap all oils and sediments, and the brew is full-bodied and flavorful.
Health considerations – In addition to the richness of the coffee, the high-quality paper filters also filter out diterpenes or coffee oils, which are known to raise low LDL or bad cholesterol levels. The metal filters will not filter oils; some believe the oils are unsafe unless you prefer the richness of the coffee oils, especially if you are a moderate coffee drinker.
Ease of use – The single-use paper filters are the easiest to use out of the three main types of coffee filters.
Are coffee filters environment-friendly?
All coffee filters, except the disposable paper coffee filters, are eco-friendly. The most eco-friendly options are reusable cloth and metal coffee filters. However, you have to learn how best to wash the filters and how to keep them safe.
How long do coffee filters last?
Depends on the type. The paper coffee filters are only suitable for one use or coffee brew; mesh metal filters can last up to 3 months or up to 100 brews, depending on the frequency of use; and the permanent coffee filtration units last more than several months.
Are coffee filters organic?
Paper coffee filters are organic and biodegradable. While cloth filters may be organic, too, they take longer to breakdown, especially if they aren’t made of the best quality cotton materials. Metal filters are neither degradable nor organic.
Do coffee filters make a difference when making coffee?
Yes. As seen above, thick filters are ideal because they ensure a bolder, tastier, and mouthfeel coffee texture that keeps you going for more, while thin filters don’t make the tastiest coffees.
The material used and its subsequent porosity also influence the quality of the brewed coffee, while the coffee filter sizes influence the coffee machine’s type and quality.