COSORI Pressure-Activated Mug Warmer

I bought the gravity induction version, so some of my comments apply to the gravity induction feature. I was initially confused when the item didn't turn on when I pushed the power button. Try putting a cup of coffee, tea, or soup on the heater before you push the power button. If that doesn't work make sure the heater isn't sitting on a cord or other item and is on a flat surface. This cup warmer will not turn on if there is no cup on the heating plate. Several times now the unit refused to turn on when there was a cup of coffee on the heater. In every case a power cord had worked its way under the unit, and it worked when the cord was removed. Check for that sort of thing if your warmer doesn't turn on. You can select from a large range of temperatures. Very nice. It seems the industry is using the term "gravity induction" for these items. This seems dishonest to me. It may be technically correct, but I have an induction stove, and associate the term induction with that type of technology. To me it implies you are getting some remarkable technology that you are not getting. When used for these devices it means it has a weight activated switch. When you lift the cup off of the heater the lights start blinking. It does not actually turn off immediately. When you put the cup back on the device the lights will stop blinking and heating is resumed. It will turn off if the cup is removed for a long period of time. I have not found that this is a problem. I will say that I see no purpose in the "gravity induction" feature if you can remember to turn the unit off when you are done with it; it will only be a source of problems. I don't believe it turns the heater off when you remove the cup and turns the unit on again when the cup is replaced. I believe it only turns the unit off if the cup is removed for a longer period of time. You don't really want the heater to be turned off when the cup is temporarily removed. The heater is a very low powered one. It is powered by USB after all. When the unit is first turned on you can watch the heat slowly climb up to the temperature you set. I have found two brands of cups that work well with the Cosori beverage warmer. There are advantages and disadvantages with both. The Cosori stainless steel cups are well made and look nice. I use coffee creamer and do not fill the cup clear to the top. The cup rim has not burned my lips. I believe these should be dishwasher safe. But the coffee cools very quickly when not on the warmer. I drink half a cup at a table with no warmer before going to a place where I have access to a warmer. So I consider this to be a problem. The Cosori will warm a cold cup of coffee however. The Cosori cup is a light cup and the unit will not turn on if there is only a little coffee in the cup. The gravity switch is on the bottom of the unit toward the back, so moving the cup toward the back of the heating plate helps a little. The Howay cups are a flat bottomed ceramic cup with a steel plate on the bottom. Your beverage will stay warm much longer in this cup. It is made for coffee warmers. It does have a wood handle, so I wouldn't put it in the dishwasher. Because of my habits the Howay cups work better for me. These cups are heavy enough to activate the unit when there is no coffee in the cup. Heating efficiency of these units depends on the design of the cups used. The Howay cups need a higher heater temperature than the Cosori cups to achieve the same coffee temperature. Mixing cup types means you would have to keep changing the heater temperature to achieve the beverage temperature you want. I would recommend selecting one cup type and sticking with that.

This is the best ever beverage warmer I have found!!! I have tested a few beverage warmers and let me tell you if you are like me and love to drink your coffee HOT this is the product for you!!! Do not skip this one!! It gets hot and stays not. Yes, it does take a moment to get to optimal temp but on the way, it is keeping your beverage hot. This product performs just as marketed. Thank you so very much for giving me what I expected when I purchased this. I wanted a HOT cup of coffee and that is what I had all day long. I LOVE THIS PRODUCT!! This outperformed my thermal canister. It also looks classy while sitting on my desk. I have the original one that goes to 230 degrees F. I do believe the newer one will work fine even at the lower level because this one gets so very hot and stays so very hot all day. Most people I would think would turn it down a bit. That is how hot it stays. For me, I enjoy it fresh out of the pot hot. COSORI states on the box, No Judgement. I can have my coffee Extra Hot. That is just how I like it too! Thank you COSORI! I would suggest getting the set if you do not have a flat-bottom mug. It will even warm up the other mugs but it will take a longer time. I tested the tall mug and it did get almost boiling hot after a good while. One note I do have for improvement is there should be a one-button selection to keep the desired temperature set so you are not guessing what one is set. Or you do not have to do the three taps to get to the desired temperature. I want mine to stay on the hottest one. You tend to stare and watch "paint dry" as the digits go up.

Works very well overall. However, the built-in cup sensor (a switch underneath that engages only when enough weight is placed on the device) is too stiff—you need a very large cup filled with coffee or liquid to activate it. Luckily, there's an option to turn off the sensor, which I did. This setting is a must for most users, I think. I also switched the temperature readings to Celsius, as that makes the most sense to me for liquids and coffee temperatures. Other than those two minor gripes, it functions well as a warmer. The timer is fixed at 8 hours, so it's only helpful if I forget to turn it off. The surface temperature of the unit runs hotter than the indicated temperature by a good 6–7 degrees C. This is fine, since much of the heat transfers through the cup and into the liquid well below the set temperature—meaning a setting of 60°C will provide about 67°C at the plate, but your coffee likely won't exceed 50°C.

Got this to keep my sourdough starter warm, as it’s way too cold in my house this deep in winter and it’s working GREAT. I set it to 94 degrees and Breadward Cullen stays at a steady 75, allowing him to thrive in the freezing New York winter. It stays on super long does auto shut off after a while, so keep an eye on it but definitely recommend for this trying to create or maintain a starter in cold weather!! It’s way cheaper and smaller than a proofing box.

there is a little button on the bottom of the warmer that pushes when you put weight on the warmer. they call this "gravity induction technology" it's meant to be a safety feature so it shuts off when you take your mug off the warmer. the problem is that it requires way too much weight. i had to push down on it with my hand for it to turn on. a large mug filled with liquid is not nearly enough weight to press the button. so the warmer was basically useless for me. i returned it. i'm surprised more people haven't commented on this defect that renders the product completely useless.

Opened in great condition, no issues. Read the instructions, twice, as there are some quirky operating aspects with this unit. Its not intuitive. I fully tested all the features, and they all work correctly in accordance with the instructions. It works perfectly as per the manual. Such as, you have to have enough weight on the heating pad to make the unit work at all or to even just adjust the temperatures up or down. The cup has to be heavy enough to operate the controls. If your cup gets too light in weight as you drink, and the cup with contents weight drops below the minimum weight, the unit will stop heating. I use it for keeping my butter soft in winter. My butter dish weighs more than the minimum, so the unit will operate even if empty. Its the only unit I could find that was this small, therefore has the lowest electricity usage, therefore the lowest long term operating cost. Its the only one with a low operating temperature that you can set by 1 degree from 25C-90C. It specifically starts to operate at 25C up to almost boiling. Butter is soft at 25-29C, and starts to melt at 30-32C. If you have a small amount of butter (mass), then I can set it at 25C and the butter is soft, but not mushy, or melted. But if you add butter, 1 cup, then I need to increase the indicated temperature to 29C. to compensate for the increase of mass. It takes about 15-30 minutes to get fully soft from a cold start at 18C (morning house temperature) and it has to heat up the butter dish and ceramic top. Works perfectly. I get up in the morning to let the dog out, I turn the unit on by touching the red button on the way by to the door. Look after the dog, start coffee, start breakfast, butter is now soft enough by the time the toast pops. Perfect. Shuts off around 2pm 8 hours later. Need to turn it back on when I start working on supper. Its ready to go when I need it, soft spreadable butter. Shuts off automatically again in 8 hrs if I forget to turn it myself. If I don't use it during the weekend, its off automatically saving electricity. Perfect. Almost all the complaints I have read about this unit is due to folks not reading the instructions or following the instructions properly that they have read. I also plan to use it for keeping my bread dough bowl warm during the rise. Set for 30C. Heat my ceramic bowl with hot water, dry, grease/butter the inside, then place it on the COSORI heat element at 30C. Drop my dough into the bowl to rise. The bowl bottom matches the same size as the COSORI heat element face. Perfect. I also liked that the cord was not a full 110V cord, but a 12V cord coming from a transformer unit that I plug into the top of my stove. The wire easily tucks behind the unit , down the wall behind the stove, almost invisible while the unit is on the kitchen counter beside the toaster. If I want to unplug it, the 12v plug comes out of the back like a laptop. Wash it, clean it, wipe it easily with no cord, then plug it back in at the toaster where it sits. Perfect. I can't believe they don't market it just for this purpose. In Canada this is almost always an issue, hard butter in winter. I now don't have to wait until summer or travel south of Mobile, Alabama to have soft butter for breakfast.

Excellent product, does what it says.

Amazing quality and really thrilled with it

I like the products features although it would be good to also have an option to use this with a high amperage lithium battery alongside the plug in. It has the highest heat I could find, so I ordered this one. It will not keep the tea/coffee hot enough for me. It will keep it just above warm, and and it gets warmer as level of tea goes lower. It says to use a flat bottom mug for maximum heat, but there are no flat bottom mugs around except metal camping mugs. I prefer to drink out of a ceramic or glass mug, so that is not an option for me. Also love the fact that it switches off on its own when not in use, but stays on long enough when going to refill my mug. At $60 however, it is overpriced as there is not much to it. $35 would be a better more sensible price.

Product is good but in order to be used you have to buy a converter due to the fact the plug is a US spec