How to choose paper filters

Choose the filter by the shape of your brewer first, then by size, then by paper color. A cone brewer needs cone filters (commonly #2 for one to two cups and #4 for larger brewers). A flat-bottom basket needs basket filters. Bleached or unbleached matters much less than most packaging suggests, as long as you rinse the paper with hot water before brewing.

What shape of filter does your brewer take?

The shape on the box has to match the shape of the brewer. A wrong fit folds over, lets grounds slip into the cup, or bypasses the coffee bed. Check the brewer or the manual before you buy anything.

Sizes vary between makers, so read the box rather than assuming a number. If you are not sure, take the old filter to the store or look up the brewer's model number.

Bleached or unbleached filters?

Both work. Bleached paper is white and usually has little taste. Unbleached paper is brown and can add a faint papery taste if you skip the rinse. Rinsing means running hot water through the folded filter in the brewer before you add coffee, then discarding that water. It takes ten seconds and removes most of the paper taste whichever you buy. It also warms the brewer, which helps hold the temperature.

If the box says oxygen-bleached or chlorine-free, that describes how it was made, and it is a matter of personal preference. We do not make any taste claim for either.

What about metal and cloth filters?

Paper is not your only choice. A reusable metal mesh lets more oil and some fine grounds into the cup, so the coffee is heavier and a little cloudy. Cloth sits in between and needs washing and storing wet. Paper gives the cleanest cup and the easiest cleanup. If you like a thick, rich mug, try metal. If you drink lighter, fruitier coffees, paper shows more of the notes.

Paper filters also change how much you grind. A thick Chemex paper slows the water, which is why the grind is coarser, as in our Chemex ratio post. A thin basket paper flows faster. Details for the other brewers are in Clever Dripper ratio and AeroPress ratio.

How do you rinse a paper filter?

1. Fold or seat the filter in the empty brewer so it sits flat against the sides.
2. Pour hot water through it until the whole paper is wet, about a cup of water for a small brewer.
3. Pour the rinse water out of the carafe or mug, then add your grounds.

This also preheats the carafe, so the first minutes of the brew do not lose heat. Skip it only if you are in a hurry, and expect a slightly flatter cup.

How many filters do you need, and how should you store them?

One filter makes one pot. A box of 100 lasts a typical household a few months. Keep the box closed and dry, away from the stove and away from anything with a strong smell, since paper picks up odors. Do not reuse a paper filter. Used grounds and wet paper are best tossed or composted the same day.

If the coffee drips slowly or overflows, the filter may not be the problem. A dirty machine does the same. Our guide to how to descale a drip coffee maker covers that fix.

What should you brew with it?

A new filter deserves a coffee that is easy to get right. No. 1 Common Sense is the roaster's pick for the cup you make every morning without thinking about it. The roaster suggests drip or French press at 60 g per litre, and says it takes milk without falling apart. The label lists cocoa, red apple and brown sugar.

It is $28 for 12 oz with free US shipping, whole bean or ground. If you brew every day, the subscription is 11% off, with skip or cancel in one click. For the amounts per cup, see how much coffee per cup, and for a first brew by hand, pour-over for beginners. All ten bags are at all ten coffees.

Buy the box that matches the brewer, rinse the first filter, and then think about the rest.