Water temperature is one of those things that is easy to ignore until a cup tastes off and nothing else explains it. It controls how quickly flavor comes out of the grounds, so a few degrees can be the difference between a cup that tastes thin and sour and one that tastes sweet and complete.
Here is the range that works for most brewing, how to adjust it by roast and method, and how to get close without a fancy kettle.
The basic range: 195 to 205°F
For most hot brewing, water between about 195°F and 205°F (roughly 90 to 96°C) does the job. That is the range the Specialty Coffee Association recommends, and it holds up at home. Hotter water extracts faster. Cooler water extracts slower.
Below that range, coffee tends to under-extract. The cup can taste sour, thin, or a little hollow. Right at a hard boil, some coffees, especially darker roasts, can come out harsh or bitter.
Adjust for the roast
- Light roasts: go hotter, around 200 to 205°F. Lighter beans are denser and give up their flavor more slowly, so they need the extra heat.
- Medium roasts: around 197 to 202°F is a comfortable middle.
- Dark roasts: go a bit cooler, around 190 to 196°F. Darker beans are more porous and extract easily, and cooler water keeps the bitter edges in check.
Starting points by brew method
- Pour-over and Chemex: 200 to 205°F for light and medium roasts. The water cools a little as it moves through the bed, so starting hot helps.
- Drip machine: most good machines heat to around 195 to 205°F on their own. If yours runs cool, a finer grind can make up some of the difference.
- French press: around 200°F. The grounds sit in the water for four minutes, so you do not need it ripping hot.
- AeroPress: anywhere from about 175 to 205°F. Lower temperatures make a softer, rounder cup and are a good place to experiment.
- Espresso: usually 195 to 203°F, set on the machine.
- Cold brew: cold or room temperature water, with a long steep of 12 to 24 hours doing the work heat normally would.
No thermometer? Use the off-boil method
Bring the water to a boil, take it off the heat, and wait about 30 seconds. That lands you close to 200 to 205°F, which is right for most light and medium coffees. For darker roasts, give it a minute or so. A kettle with a temperature setting makes this easier, but it is not required.
If you live at elevation, keep in mind that water boils at a lower temperature the higher you go, roughly 1°F lower for every 500 feet. At 5,000 feet, boiling water is already only around 202°F, so you can pour it right off the boil.
How to tell if temperature is the problem
- Sour, thin, or flat: try hotter water, or a finer grind.
- Bitter, harsh, or drying: try slightly cooler water, or a coarser grind.
Temperature and grind both change extraction, so change one at a time. Keep your ratio the same while you adjust, and the difference will be easier to taste.
We roast in small batches and ship whole bean, so you can grind fresh and match your water to the roast in your bag.
The short version
Aim for 195 to 205°F. Go hotter for light roasts and cooler for dark ones. Without a thermometer, wait about 30 seconds off the boil. If the cup is sour, go hotter. If it is harsh, go a little cooler.