How to Keep Chemex Warm

The Chemex is a simple, elegant, and affordable way to brew coffee. Unfortunately, the coffee cools down quickly because there’s no heat source other than your hand (which isn’t much of a source). So it’s essential to know how to keep a Chemex warm until you’re ready to drink it.

How to Keep a Chemex Warm

Prewarm the carafe by pouring hot water into it and giving it a rest for a couple of minutes, swirling to rinse out any residue, then pouring out the hot water. Do this before brewing, so the carafe is still hot when you pour the coffee into it.

A person stands in front of the different types of coffee makers and white bowls on top of a stainless table

Use a Heat Pad or Heatproof Mat

A heating pad or heatproof mat will keep your Chemex warm without ruining its wood surface. Simply place the mat on top of your Chemex and plug it in. This option is ideal for people who want to keep their Chemex warm for long periods — like at work or home — because it doesn’t require as much babysitting as other methods (like leaving a pot of water on the stove).

Preheat the Chemex

Preheating the carafe and the brewer is key to keeping your Chemex warm. You can pour hot water through the filter for a few seconds. If you have a French press, try doing this in advance and then simply pour out some of the hot water before brewing your coffee.

Once your Chemex has been heated up, it’ll stay warm for about 20 minutes—just enough time for you to enjoy a cup of freshly brewed coffee!

Use a Coffee Sock

An excellent way to keep your coffee warm is to use a coffee sock designed specifically for the Chemex to keep the heat in and prevent it from escaping. These cozies can be found at most stores that sell Chemex products, or they can be purchased online through Amazon or other retailers. They come in different colors and patterns, so they don’t just look nice; they also function well!

Use a Lid

The most obvious way to keep your coffee warm is to use a lid on your Chemex. This will keep the heat in longer than just pouring it into a regular mug or cup. The lid fits on top of the glass body and has a silicone band to ensure that nothing leaks out when you pour hot liquid into it.

A lid will also keep dust out of your coffee while you wait for it to cool down, as well as protect against spills if you accidentally knock over your cup while pouring yourself a drink.

Use a Glass Stopper

Another way to keep your Chemex warm is by using glass stoppers instead of lids on top of them. If you’re using a glass stopper, it’s best to use one that has a rubber seal. The stoppers that come with the Chemex are wood and have no rubber seal.

To keep your coffee warm, you need to put something between the glass and your cup, so it doesn’t slide off. If you don’t want to deal with this extra step, I recommend getting a silicone seal for your glass stopper.

Use a Wool or Soft Fleece Mug Cover

You can keep your Chemex warm with a cozy mug. This simple device slips over the top of your mug, trapping heat inside it so it doesn’t cool down too quickly. You can buy these online or at any local craft store. They’re inexpensive and easy to use.

If you don’t want to buy a new mug cozy, you could also try making one yourself using an old sock or bandana! Just cut a hole in the top of the sock or bandana so it fits around your cup, and tie some string around it so that when you put it on your cup, it will stay put.

Brew the Right Amount of Coffee

Brewing less coffee at once is one way to guarantee that it is always hot. If you want more coffee, you’ll have to brew it again. The upside is that you can drink it while it’s still hot.

Immerse in Warm Water

According to a study, the ideal temperature for coffee is 136 degrees Fahrenheit. It should not be too hot so that your mouth gets burned while still being warm enough so that you can feel the delicate aroma of the coffee. One of the best ways to keep your Chemex at this temperature is to put it in a warm water bath.

  1. The first thing you need to do is boil some water in your kettle or on your stove. The kettle should have enough water to fill it up about halfway.
  2. Once the water boils, pour it into a vessel that can hold the Chemex along with its filter and grounds.
  3. A Pyrex casserole dish works well for this purpose.
Chemex pour-over glass coffeemaker with a natural wood collar on top of a brown wooden table

Place the Chemex on top of whatever vessel you’re using for your hot water bath and let it sit for an hour. The longer it sits there, the warmer it’ll get. If you want to speed things up, you can put a little more boiling water in after an hour or so has passed; just make sure that the temperature doesn’t go above 200 degrees Fahrenheit.

Why Does the Chemex Lose Heat That Fast?

The Chemex was designed intentionally by Bunn-O-Matic because they wanted people to be able to see their coffee brewing so they wouldn’t be tempted to just pour hot water into their cup and add coffee grounds into it. However, their design’s downside is that it loses heat too fast. Why?

  • The Chemex loses heat fast because of its thin walls and the fact that it doesn’t have a warming plate.
  • The Chemex has a wide bottom and straight sides that allow more contact with the table surface. This makes it easier to cool down than the traditional hourglass shape that many thermal carafes have.
  • Also, when you pour out of the Chemex into another vessel or mug, you tend to lose some of the heat from the coffee through radiation as the coffee gets into contact with the air around it.

Related Questions

Can You Warm up a Chemex in the Microwave?

It is not recommended to warm up Chemex in the microwave because the glass may get damaged due to heating. The heat from the microwave may also change the taste of your coffee. Microwaves don’t heat evenly throughout the vessel. The water closest to the surface heats first, while the water in the center remains cold.

Does a Chemex Keep Coffee Warm?

Chemex brewers don’t keep the coffee warm very well. Chemex coffee should be consumed immediately, as it was intended to be. If you want your coffee to stay warm, you can use an insulated carafe instead of the traditional glass carafe that comes with the Chemex.

How Long Does Coffee Stay Warm in a Chemex Carafe?

Coffee can stay warm in a Chemex for about 30 minutes. However, there are certain factors to consider when deciding how long coffee will stay warm: the presence of glass insulation, the size of the Chemex, how often you pour from the carafe, and how quickly you pour.


There are many ways to keep your Chemex warm. You can preheat the cup and/or carafe beforehand, use a glass stopper, use a Chemex Cozy or Chemex Mug Cozy, and warm the Chemex coffee on gas, glass, or electric coil stove.