The Best Slow Cookers

A slow cooker promises to be a little fantasy grandmother who sits in the kitchen all day cooking for you, but use the wrong cooker and that dream could fizzle. A cooker might run hotter than expected, drying out the food or turning it mushy, or slower than you want, so dinner isn’t ready when you are. Then there can be issues with hot spots, which make food cook unevenly. And what if operating your machine is so confusing that you have to pore over the manual each time you use it?

A well-designed slow cooker excels in covered, moist-heat cooking, also known as braising. This technique is beneficial for meat—usually tough, cheap cuts that tenderize through long, gentle cooking. When connective tissue, which is made mostly of collagen, is cooked beyond 140 degrees, it begins to break down into gelatin, the protein that makes for tender meat. Collagen breaks down most efficiently in a moist environment at temperatures around 200 degrees. This lower-than-boiling temperature range is also good for developing deep, complex flavors in soups, stews, and sauces. 

Most slow cookers come with two settings: low and high. The two settings give cooks flexibility: You can either cook for a shorter span on high or about twice as long on low. Generally the choice is about convenience, not flavor or texture, though delicate foods often require the low setting. Frequently we have found that slow cookers reach the same final temperature on either setting but take longer to do so on the low setting than they do on the high setting. 

 We wanted a slow cooker that would deliver a properly cooked meal and be simple and intuitive to use. Previous testing taught us that glass lids were a must so that you can see progress without opening the lid, which lets heat escape and slows down cooking. We also prefer oval- and rectangular-shaped crocks, which can accommodate large roasts; provide abundant surface area to successfully slow-cook rice, grains, and beans; and generally offer more versatility than round crocks. A generous 6- to 7-quart stated capacity was a must—the same capacity as the Dutch oven we’d otherwise use for similar tasks. Few slow cookers actually hold as much as their stated capacity, but we’ve found them to be adequate for all tasks regardless. 

We learned more about the differences between how the types are heated when we dismantled a set of cookers with the help of Gregory Thiel, a postdoctoral associate in mechanical engineering at the Massachusetts Institute of Technology. Traditional slow cookers have thick, heat-retaining ceramic vessels that absorb and transmit heat gradually. They’re warmed by a thin heating element strip made of nickel and chromium (or “nichrome”) that wraps around the vessel like a belt. When the cooker is on, this wire heats up more or less powerfully depending on the wattage and the setting.

Hot plate–style slow cookers feature a crock that sits on an electric heating element in the base that acts like an enclosed burner. Their crocks are typically made from thin metal (usually aluminum) that often has a nonstick coating.

More recently, a new type of slow cooker has emerged. It uses a cast-iron Dutch oven as a crock and is heated the same way as hot plate–style slow cookers with an electric base. These Dutch oven slow cookers are often labeled as “multicookers,” but this is a bit of a misnomer since you can’t pressure-cook in them as you can in a true multicooker. 

There are pros and cons to each style. Traditional slow cookers tend to be a bit more affordable, often costing less than $100. Because their crocks are made of ceramic, they can crack if dropped or sharply struck, but they are otherwise durable. You can’t brown or sauté in ceramic crocks; you must brown food in a skillet on the stove and transfer food to the slow cooker. We’ve found that some heat unevenly too; as you’ll see below, top-performing traditional slow cookers have extra insulation to limit hot spots.

Hot plate–style slow cookers are typically a bit pricier, starting at around $200. Their thin aluminum crocks can be easier to use because they are lightweight and won’t crack, and their nonstick coating makes them easier to clean. They let you sauté and brown food right in the crock, no separate skillet needed. While it’s convenient to sauté food right in the cooker, it’s important to note that models with metal crocks often slow-cook much faster than models with ceramic crocks: first, because they are often starting hot after sautéing, and second, because models with thin metal crocks heat up faster than ones with thick ceramic, especially when the entire metal crock bottom rests on a large heating element. As a consequence, with a metal crock, if you don’t pay close attention, you can easily overcook food. It’s important to check for doneness earlier than indicated in most recipes, which are usually developed in ceramic slow cookers.

Dutch oven slow cookers can be a versatile investment—they combine a slow cooker and a Dutch oven into a single unit—but they are heavier and harder to lift.

Maybe. On the plus side, Dutch oven slow cookers are versatile. The Dutch ovens that come with the units can be used separately, either on the stove or in the oven. The Dutch ovens themselves performed well on their own, though they’re smaller than we generally prefer—about 5 quarts instead of 7.

Some of the Dutch ovens worked well as slow cookers too. A Dutch oven slow cooker can be a good option if you want to be able to sear and sauté directly in your slow cooker but would prefer not to use the nonstick-coated crocks that come with other hot plate–style slow cookers.

One downside is that unlike traditional oval-shaped slow-cooker crocks, cast-iron Dutch oven inserts are round, making it hard to fit long pieces of food, such as brisket. And cast-iron Dutch ovens are much heavier than even traditional ceramic slow cooker crocks, so they can be a bit more difficult to lift, especially when filled with food.

In addition, Dutch oven slow cookers may save a little storage space, but they’re unlikely to save you much money, as they cost at least $300 to $650, or roughly the same to twice as much as it would cost to get both our Best Buy Dutch oven and our winning hot plate-style slow cooker. Ultimately, we think our top choice in this category, the All-Clad 6-in-1 Digital Slow Cooker with Enameled Cast Iron Pot, is best for people who want to get both a midsize Dutch oven and a slow cooker but have limited storage space. Most people would be better off buying a Dutch oven and slow cooker separately because our favorites in both categories perform better and are easier to use than an all-in-one product.

• Simple, Intuitive Controls: A few models were a pleasure to use, with controls that were unambiguous and buttons that clicked satisfyingly and lit up when pressed and indicated that cooking had started.

• Internal Temperature Sensor and Control: Our temperature tests revealed that better slow cookers had internal temperature sensors and controls. That meant that they cooked more gently and successfully than slow cookers without temperature controls (which simply keep heat fully on until food boils at 212 F, with predictably rubbery, overcooked results). Cookers with sensors kept food at a braising temperature, just below boiling, so the foods cooked gently and became tender while retaining their juiciness. Note: You can’t see this feature when you’re shopping, but our testing results (using a temperature probe suspended in water in the slow cooker over hours of cooking on low and high settings) clearly indicated which models had internal controls and heated gradually to cook more gently and successfully. 

• Large, Stay-Cool Handles: Crocks with handles that were easy to grasp securely and stayed cool were easier to use.

• For Traditional Models—Good Insulation: Traditional slow cookers can sometimes heat unevenly, with hot spots around the belt-shaped heating element that surrounds the ceramic crock. When we dismantled all the crock pots, we found that the traditional slow cookers that performed best had thick, heat-resistant padding and foil heat shields packed inside. The other traditional models were empty except for the heating element. The insulation buffered the crocks from contact with the heating elements, preventing hot spots and promoting even cooking. It also explained why some of those models, including one of our favorites, tended to run a bit slower.

• Attached Temperature Probe: One model had an attached probe that accurately measured the temperature of food cooking inside the slow cooker. While it’s possible to slow-cook successfully without this feature, we appreciated that the probe let us monitor food safety and cooking progress without opening the lid. This is important because slow cookers typically cook very gently, and every time you open the lid to stir or check food, you lose considerable heat, which lengthens the cooking time. The model that came with this temperature probe had three ports in the lid with tight silicone gaskets that kept heat in but allowed us to insert the probe in different locations as needed. The probe stored neatly in the handle when not in use, so we didn’t risk losing it.

• Latching Lids and Silicone Gaskets: Since we often take a slow cooker to a potluck or other occasion, we liked models that had latching lids and silicone gaskets around those lids, which helped prevent leaks in transit.

• “Hold Temperature” Feature: One model can hold food at your desired temperature for up to 24 hours. This feature lets you use the slow cooker to reheat leftovers, as a fondue pot, or as a yogurt maker. While the manufacturer claims this also allows you to use it as a sous vide cooker, it lacks a propeller to circulate water around the food, which you’d find with dedicated sous vide immersion circulators.

• Overcomplicated Displays: You really shouldn’t need the manual after the first time you use a slow cooker. We wanted intuitive controls, but several models had so many buttons with such confusing layouts that our testers couldn’t tell if they’d set them correctly or even whether they were on.