Coffee Filter Sizes Explained: What You Need To Know
Brewing coffee filter sizes explained. What is available, what they are made from, their different shapes and how they affect the flavor of your brew.
You could not be blamed for thinking that choosing a suitable coffee filter should be a quick and simple task.
Unfortunately, with choices between:
- type of material
- shape and size
and the question of:
- how all of these might or might not be compatible with my home brewing process
- how these might or might not affect the taste of my cup of coffee
the decision becomes slightly more complicated than you may wish.
If your home coffee brewing involves the use of an automated coffee machine, the choice of a filter may be restricted to the type recommended and/or compatible with your machine.
But if you enjoy a little more control over your brewing process this article will help clear up any confusion you may have with regards to coffee filters.
For the purposes of this introduction, coffee filters types can be divided into:
- Metal
- Paper
- Fabric/cloth
Shape-wise, coffee filters can typically be divided into conical, bucket, or disk.
Finally, the coffee filter size can be divided into #1, #2, #4, and #6 for the cone variety.
Bucket shaped filters are generally sold in 8 to 12 different sizes.
Why Coffee Filters Are Required?
Coffee filters essentially serve an important singular purpose. That is – separating the liquid coffee extract from the coffee grounds.
Let us be honest, no cup of coffee is going to be enjoyable with a thick layer of coffee grounds settled at the bottom of your cup like mud.
Coffee filters work by presenting a physical barrier to solid coffee grounds. The filter only allows the liquid coffee extract with all its delicious compounds and flavors to pass through.
If paper filters are used they will have a slight impact on the texture and taste of your coffee. Paper filters out much of the microscopic coffee grounds and some of the coffee oils.
Paper filters were invented in 1908 by Melitta Bentz, a German housewife. She didn’t enjoy the bitter taste in her cups of coffee prepared by boiling loose coffee grounds in water.
Prior to paper, linen or fabric was the traditional filtration material used.
Coffee Filter Sizes Explained Simply
The size of the coffee filter you may need to purchase will closely depend on your brewing process and/or the brewing equipment you use at home.
Some brewing equipment will employ a permanent, typically metal, filter. If this is what you use at home you will have no need to concern yourself with filter sizes.
If your brewing equipment uses disposable, generally paper or fabric, filters then your equipment should be marked with the filter size required for proper functionality.
Bucket Filters
Bucket filters are sold in 8 to 12 different sizes.
These different sizes are closely linked to the cup brewing capacity of your electric or non-electric coffee equipment.
Cone Filters
The more common cone coffee filter sizes are #1, #2, #4, and #6.
- Number 1 (#1) size is for the small one-cup coffeemakers.
- Number 2 (#2) size filters work with electric coffeemakers equipped with four to six cups, as well as two-cup non-electric makers.
- Number 4 (#4) size filters fit electric coffeemakers with eight to 12-cup capacities.
- Number 6 (#6) size filters work with 10-cup non-electric coffeemakers.
Again, the filter size that your equipment needs should be clearly marked on the device or published on the device’s packaging.
What Are Coffee Filters Made From?
As mentioned above, modern coffee filter types are either paper, fabric, or metal.
Paper filters are designed to be disposable while metal filters are meant to be permanent.
Fabric or cloth filters are a middle ground between paper and metal. They are designed for long-term, but not permanent use.
Paper Coffee Filters
These are the type of filters that most people think of with regards to home coffee brewing. They are the most readily available at the majority of retail outlets that sell either coffee or coffee brewing equipment.
While these filters may be the cheapest option initially. However, the fact that they are designed to be used once then disposed of means the overall cost will escalate quickly over time.
Paper filters are tightly woven and absorbent. This means they filter out not only the solid coffee grounds but much of the coffee sediment or microscopic coffee grounds.
Being absorbent, paper filters also tend to filter out some of the less soluble coffee oils. This all adds up to a cup of coffee that is light, crisp, bright, and clean as far as flavor is concerned.
Generally, there is an increasing global trend towards a preference for a fuller, thicker, and richer coffee flavor. Due to this paper filters are slowly losing the popularity they once enjoyed.
Paper filters are sold in two varieties, namely bleached and unbleached.
Bleached paper filters have that unnatural bright white look as opposed to the more brown looking unbleached variety.
Bleaching is done using either chlorine or oxygen. Oxygen bleaching produces a product that is safer for the environment.
Both varieties perform the exact same function with no discernible taste difference.
While both are biodegradable, the unbleached paper filters are more environmentally friendly. This may be an important factor to many nowadays considering they are designed to be disposable.
Benefits Of Paper Filters
- Flavor Profile: light, crisp, bright, clean
- Clean-up: quick, convenient
- Waste: high
Fabric/Cloth Coffee Filters
Between paper and metal, fabric or cloth filters are the most traditional with the longest use historically speaking.
They have a finer weave than metal filters but are not as absorbent as paper. This translates into a filtration process that filters out all the solid coffee grounds and much of the coffee sediment or microscopic coffee grounds.
It does allow almost all the coffee oils to pass through. This means a cup of coffee that is aromatic, clean, bright, and with a medium body or texture is produced.
While paper filters are designed to be used once before disposal, fabric filters can safely be used a few dozen times before they negatively affect the taste of your coffee.
They can be used about 100 times. Thoroughly wash between each brewing process before disposal becomes a requirement.
Benefits Of Cloth Filters
- Flavor Profile: aromatic, clean, bright, medium body
- Clean-up: 30 to 60 seconds
- Waste: minimal
Metal Coffee Filters
Metal filters will filter out all the solid coffee grounds.
They do allow much of the coffee sediment or microscopic coffee grounds to pass through as well as many of the coffee oils. This results in a cup of coffee with the fullest and richest flavor and heavy body texture.
It is primarily for this reason that the popularity of this type of coffee filter is on the increase.
However, it should be noted that metal filters are the most expensive option upfront.
They do require cleaning between each and every brewing process. In addition, they are not available for use in many models of automatic coffee-makers.
But they are an excellent choice for those who enjoy a more hands-on approach to their coffee brewing.
On the positive side, if well looked after, they can last a lifetime and in the long term are good for the environment.
Benefits of Metal Coffee Filters
- Flavor Profile: aromatic, bold, rich, heavy
- Clean-up: 30 to 60 seconds
- Waste: zero
Different Coffee Filter Shapes
As mentioned above the three main filter shapes that are available are cone, basket, and disk. The cone-shaped filter being the most popular among dedicated home brewers.
Only you can decide which are the best coffee filters for you and your needs.
Here are the three types of coffee filters available.
Basket Shaped Coffee Filters
These coffee filters may be the type most people with automatic coffee-makers are familiar with.
They are shaped like cupcake holders with a flat base smaller in diameter than the top opening. While made primarily out of paper, they are also available in metal.
Many coffee connoisseurs argue that these types of filters do not cater for the best possible coffee extraction. This is because they do not allow for the maximum contact between coffee and water.
Cone Shaped Coffee Filters
These coffee filters are available in two varieties.
The traditional cone shape like that of a party hat and the cone shape that results in a short flat edge at the bottom.
The second variety is usually found in some automatic coffee-makers.
These types of filters are available in paper, fabric, and metal.
The cone-shaped filter is most popular with dedicated home brewers believing it filters coffee the best.
This is primarily due to the fact that this shape is believed to offer the best coffee to water contact. The result is considered the most effective coffee extraction.
Cone coffee filters are very popular with cold brew enthusiasts who use the steeping brewing method.
Disk Shaped Coffee Filters
These coffee filters are available mostly for Aeropress coffee brewers. Also as replacements for some French Press brewing equipment.
They are flat disks and are usually made of metal. As a result, they are generally only available for specific brewing tools.
Substitute Coffee Filters
Coffee has been prepared and drunk long before coffee filters were manufactured.
So if you find yourself in desperate need of that cup of coffee, but have run out of filters, there are several suitable substitutes.
- Instant Coffee
Instant coffee may not be as tasty as that cup made from freshly roasted coffee beans, but it can serve as a more than suitable alternative.
The best part is that it can be prepared without any need for filters. So, as a backup plan, consider keeping a bottle in your pantry.
- French Press
Many coffee connoisseurs use this piece of brewing equipment and nothing else.
The benefit is that it has its own built-in permanent filter.
Do you rely on your automatic coffee-maker every morning, but have run out of paper filters? A French Press will certainly make you a delicious cup of coffee.
Consider buying one and learning how to use it.
You may find yourself selling that fancy coffee-maker.
- Cowboy Coffee
Yes, that coffee you may have seen being brewed in many a western movie. No filters are required, but if not done properly can taste terrible.
- Add water to your pot and bring it to a boil.
- Once the water’s boiling, remove the pot from your fire or heat source and let it sit for 30 seconds. This will lower the water temperature to 930 degrees C (2000 degrees F) – the perfect temperature for brewing coffee.
- Add 2 tablespoons of finely ground coffee for every 236-237 ml of water.
- Stir the grounds into the water.
- Let the brew sit for 2 minutes and stir again.
- Let the coffee sit for 2 more minutes.
- After a total of 4 minutes of brewing sprinkle a little cold water on the grounds. Yes, this actually does help them settle to the bottom.
- Slowly pour the coffee, so the grounds remain at the bottom of the pot.
- Paper Towels Or Napkins
Very similar to the genuine paper coffee filters and more than suitable as an alternative.
Simply line the filter cup with a layer or two and brew as normal. It is best to use plain paper towels or napkins rather than those printed with decorations.
The printed paper towels or napkins contain unhealthy dyes. Do not use it as a permanent replacement. Even the plain variety contains chemicals that might end up in your coffee.
- Toilet Or Tissue Paper
These can also be used as a suitable alternative. Toilet paper is better than tissue paper as it is thicker and two-ply is better than single-ply.
Obviously, it is best to unpack and use a fresh roll rather than raid from the toilet area.
- Cheesecloth
This might not be an available option for many since cheesecloth is used in the making of cheese. However, it can serve as a good substitute.
Cheesecloth comes in different grades from fine to coarse. The finer the grade the better for use as a coffee filter.
- Butter Muslin Or Fine Cloth
Again many may not have access to butter muslin as it is used in the making of butter. But any finely woven cotton cloth or dish towel can serve as a suitable alternative.
Just make sure it is new and clean.
- Cotton Socks Or Stockings
Believe it or not, these have been used by many as a no alternative substitute.
You can either place your coffee grounds into the sock or stocking and while holding it over your cup pour hot water over the grounds. Or else steep the sock or stocking with coffee grounds in hot water.
If this idea does not appeal to you there are such things as reusable coffee socks available on Amazon.
- Standalone Metal Filters
There are stand alone metal coffee filters designed to sit on top of a cup or mug.
Simply place your coffee grounds in the filter, which is placed over a cup or mug. Slowly pour hot water onto the grounds.
Are Permanent Coffee Filters Better Than Paper?
This is perhaps the wrong question to ask. It is perhaps better to ask “Which coffee filter is right for me?”.
Much of it depends on how you prefer the flavor and texture of your coffee.
As mentioned above paper filters out most of the microscopic coffee grounds and many of the coffee oils. If you prefer your coffee with a light, crisp, bright, and clean flavor profile then paper filters are right for you.
However, if you prefer your coffee with an aromatic, bold, rich, and heavy flavor profile then permanent metal filters would be better.
Besides coffee flavor and texture there are cost considerations.
While paper filters might be the cheapest option, their overall cost adds up over time. They are designed to be used once then disposed of.
If well looked after, metal filters can last you a lifetime.
Environmentally speaking many may consider metal or permanent filters to be the better choice. Even though they are not biodegradable, they can be recycled.
Both bleached and unbleached paper filters are biodegradable. They still add to the enormous quantity of rubbish that needs to be buried at landfills if you live in an area that doesn’t offer recycling.
Do Coffee Filters Change The Coffee Taste?
Coffee beans are filled with a large variety of complex compounds. These all add to the rich flavor that helps make coffee such a popular beverage.
What you filter out during the brewing process will determine your cup of coffee’s final taste. So the simple answer is yes, filters do change what would be the original taste of your coffee beans.
Paper filters essentially filter the most due to their very fine weave and absorbency. This produces a light texture and flavor.
Fabric filters are the middle ground between paper and metal. They will tend to give your coffee an aromatic, clean, bright flavor with a medium body texture.
Metal filters provide the least obstructive barrier. They give your coffee a bold, rich flavor with a heavy texture.
Your coffee taste preferences will determine which type of filter you want to use.
Can You Re-use Paper Coffee Filters?
The recommendation for paper filters is “use once and discard”. The best use of a paper filter will indeed be its first use, but it is safe to re-use paper filters more than once.
Good quality paper filters can safely be used 4 or 5 times before they negatively affect the taste of your coffee. Just remember to thoroughly rinse and air dry between each brewing process.
It should be noted that once your paper filter has reached the end of its usefulness for brewing – it can be put to further use in some other ways.
Some quick suggestions are:
- arts & crafts
- keep soil from leaking out of pots and planters
- germinate seeds by placing seeds inside and moistening
- straining cooled kitchen grease
- un-stinking shoes by bundling up with baking soda and placing in the toe area
Do Paper And Fabric Coffee Filters Go Bad?
Very unlikely.
Store in a cool, dark, and dry location away from other aromatic compounds such as spices. They should be fine for use at any time.
Always thoroughly rinse and completely air dry between uses.
If you plan not to use your coffee brewing equipment for an extended period it is a good idea to remove your paper or fabric filter.
Can You Put A Paper Coffee Filter In The Compost?
Both the bleached and unbleached paper filters are biodegradable.
The unbleached variety is definitely better for the environment. However, both your paper filters and used coffee grounds should compost quickly.
