The Chemex is an hourglass-shaped borosilicate glass brewer designed in 1941 by chemist Peter Schlumbohm. Its defining feature is a proprietary paper filter 20-30% heavier than a standard pour-over filter, folded into four layers on the pouring-spout side. This thick filter strips nearly all oils and fines, producing a cup so clean it is often described as tea-like. The original design is part of the permanent collection at the Museum of Modern Art in New York.
How the Chemex brews
The Chemex combines a conical pour-over drawdown with a filter heavy enough to slow flow significantly. The four-fold side sits against the pouring spout to add restriction where the glass would otherwise let air bypass the bed. The glass body has no drip tray — the brewed coffee collects directly in the lower bulb, and the filter is lifted out when draw is complete. Because the filter absorbs water aggressively, all Chemex recipes call for a thorough pre-rinse with hot water before adding grounds.
The large, open cone allows for very gentle pouring and an even bed, but the slow drawdown means the coffee-water contact time is long — typically 4 to 6 minutes for a full batch. This favours a coarser grind than a V60 at the same dose.
Sizes in this family
Chemex sells the same shape in several capacities:
- Chemex 3 Cup — small, for 15-25 g dose.
- Chemex 6 Cup — the most popular size. Suits 30-45 g dose for one to three mugs.
- Chemex 8 Cup — larger batch, 45-60 g dose.
- Chemex 10 Cup — full batch brewing, 60-80 g dose.
All sizes use the same paper filter folded to match. "Cup" in Chemex terminology refers to a 5-oz Japanese measure, so "6 Cup" is approximately 30 oz or 900 mL total liquid capacity.
What Chemex recipes in this collection share
Because the filter dominates flow rate, Chemex recipes are less technique-sensitive than V60 recipes — what matters most is grind, dose, ratio, and total brew time. Classic recipes come from James Hoffmann, Scott Rao, and the Chemex brewing guide. Typical parameter ranges:
- Ratio: 1:14 to 1:17
- Water temperature: 92 to 96 °C
- Grind: medium-coarse (coarser than V60 at the same dose)
- Total brew time: 4:00 to 6:30
Choose Chemex when you want a very clean, delicate cup that flatters lighter roasts and floral origins, or when brewing multiple servings at once. The thicker filter makes it less suitable for dark roasts that benefit from retained oils.