Pick a coffee filter by your brewer first, not by a promised flavor. A cone paper belongs in a cone dripper or cone-style brew basket; a pleated flat-bottom paper needs a basket that supports both its base and its walls. Once the fit is right, the shape of the basket does change how the bed forms, how fast it drains and how the recipe reacts to grind and pouring.
Quick answer: A cone builds a deeper bed that narrows toward one outlet. A flat-bottom basket spreads the same dose across a wider, shallower bed. Neither shape is better for everyone. Buy the paper your brewer was designed for, then dial in that brewer rather than forcing one filter shape into the other.
Cone and flat-bottom filters compared
| Decision | Cone filter | Flat-bottom filter |
|---|---|---|
| Bed shape | Deeper, narrowing toward the outlet | Wider and shallower across a flat base |
| Paper shape | Tapered paper with a seam, sized to the cone angle | Round flat base with pleated (fluted) walls |
| Common size codes | #1, #2, #4, #6; 60° cones in 01/02/03 | No. 155 and No. 185; 8–12 cup "basket" filters for drip machines |
| Fit risk | Wrong angle or size folds, gaps or blocks the outlet | Wrong base diameter or wall height collapses or overflows |
| Starting grind | Medium-fine to medium, then adjust | Medium, then adjust for flow and taste |
| Best reason to choose it | You own a cone brewer and can buy its papers locally | You own a basket brewer and can buy its papers locally |
Treat these as starting points, not flavor rules. Hole count, ribs, paper thickness, dose, roast, grind and pour pattern all move the cup. Two flat-bottom brewers can drain quite differently, and so can two cones.
What the research does—and does not—show
A 2019 UC Davis study brewed coffee through semi-conical and flat-bottom baskets in a controlled drip system. The panel detected clear sensory differences between the two, and those differences shifted with roast level and grind size. Consumers did not agree on a winner: different groups preferred different combinations.
The fair takeaway is that basket geometry can matter. The study does not show that every cone tastes one way, every flat-bottom brewer tastes another, or that one shape wins. It used specific equipment under lab conditions, so treat broad claims like "cones are brighter" as ideas to test at home, not reasons to buy.
Drip coffee maker: cone or basket?
If you are buying filters for an automatic drip coffee maker, the machine decides for you. Pull out the brew basket and look at the bottom:
- Flat, round floor with straight sides: it takes fluted basket filters, usually sold as "8–12 cup basket" papers.
- V-shaped or wedge-shaped floor: it takes cone papers. Most 8–12 cup cone machines use #4; many smaller 2–6 cup machines use #2.
The owner's manual or the label inside the basket usually names the size. A #2 paper in a #4 basket sits too low and can let grounds bypass the paper; a #4 in a #2 basket bunches over the rim. A basket paper squeezed into a cone machine is the most common cause of overflow. If a drip machine is your only brewer, stop here and buy the matching paper—the rest of this guide is for manual pour-over.
Run this filter-fit check before buying
- Name the brewer. Write down the brand, model, stated filter format and batch size.
- Check the base shape. A round flat base and a pointed cone are not interchangeable.
- Check the size code or dimensions. "#2," "02" and "155" describe three different systems. A 60° cone paper and a Melitta-style wedge paper can both be called cones and still fit each other's brewers badly.
- Check the wall height. The paper should sit just below the rim and stay supported when wet.
- Check the outlet. The paper must not bunch into or seal the drain holes.
- Buy a small pack first. Confirm seating and drainage before you stock up.
Yozcoffee's flat-bottom basket filters come 200 to a pack for compatible basket-style brewers and hold up to 50 g of ground coffee. They are not cone papers. The 300 ml portable pour-over set specifies No. 155 flat-bottom papers and ships with ten, so you already know the replacement format.
When a cone setup makes more sense
Go with a cone when your dripper was built for it and the right paper is easy to find where you live. The 400 ml glass pour-over set uses a fitted cone paper in a ribbed glass dripper (about 10 cm across the top); papers are sold separately. The 450 ml ceramic pour-over set also takes a cone paper, but the listing does not confirm a branded size—its opening measures about 11 cm, so check a paper against that rather than ordering by server capacity.
A cone brewer is a poor buy if you already have a big supply of basket papers you want to use up. It may also frustrate travelers who can't count on finding its paper at their destination. In those cases a known flat-bottom size, or a reusable metal filter, is simpler. To compare more brewer shapes side by side, browse pour-over coffee makers and drippers.
A four-brew comparison that gives both shapes a fair chance
If you can borrow one brewer of each shape, skip the one-cup verdict. Each needs a quick dial-in before the comparison means anything. Weigh coffee and water on a coffee scale and keep the water at the same temperature for every brew—195–205°F (90–96°C) is a sensible range.
- Brew one: cone baseline. Use the coffee, water and ratio you plan to use for the flat brewer. Note the grind setting, pour pattern and total drain time.
- Brew two: flat-bottom baseline. Keep dose, water and temperature identical. Use that brewer's own paper and an even, centered-then-spiral pour that keeps the wide bed level.
- Brew three: fix the weaker cup. Change only the grind, by one small step. Don't chase the other brewer's drain time—the geometry is different.
- Brew four: repeat the better recipe. A repeat tells you more than a lucky first cup. Taste both at similar temperatures and note clarity, body, sweetness, acidity and finish without forcing a winner.
Use the coffee grind size chart only as a starting range, then let flow and taste guide the next adjustment. The 20 g pour-over recipe gives you a repeatable dose, bloom and pouring plan for both brewers.
Common mistakes
- Folding a basket paper into a cone: the creases and gaps reroute water and can block the outlet.
- Buying by carafe size: a 400 ml server tells you nothing about the paper's angle or diameter.
- Mixing up size systems: #2, 02 and 155 are not the same filter, even though all three are sold for "1–4 cups."
- Changing grind and pouring at once: you won't know which change helped.
- Treating equal drain times as equal extraction: bed depth and outlet design differ between shapes.
- Calling one shape easier for everyone: familiarity, paper supply and your recipe matter as much as geometry.
The practical choice
Start with fit, local paper supply and the batch size you actually brew. Choose a cone if a supported cone dripper or cone-basket machine suits your routine. Choose flat-bottom if you prefer that brewer, want a common size such as No. 155, or already own a compatible basket. Then dial in the system you picked on its own terms.
Product specifications checked September 22, 2026. Research reference: Frost, Ristenpart and Guinard, "Effect of Basket Geometry on the Sensory Quality and Consumer Acceptance of Drip Brewed Coffee," Journal of Food Science (2019). The cover image is AI-generated editorial photography, not a product photo or a controlled experiment.