Pressure cookers are filled with the ingredients for your meal in addition to a liquid of some kind. With the lid sealed and the heat turned on, the liquid boils, changing states into steam. The pressure cooker's sealed lid traps the steam inside where it pushes against the inner walls of the pot as well as its contents. As the steam continues to push, it increases the pressure inside the pot.

The boiling point of water is tied closely to the amount of pressure placed on the water. If you've ever traveled to high altitudes, you may have noticed that you could bring water to a boil more quickly than you can at lower altitudes. The water can boil faster because there is less atmospheric pressure at high altitudes, resulting in lower boiling points. A pressure cooker works on the same concept in reverse, increasing pressure and in doing so increasing the boiling temperature of water. At 15 psi, the boiling point of water can reach 250 °F, a big step up from the standard 212 °F. The higher water temperature accelerates the cooking process, making it quick and easy to get dinner on the table.

The simplicity and safety of electric pressure cookers make them an excellent choice. Digital controls allow you to set your desired temperature or pressure and let the cooker handle the rest. If your top priority is making meal prep easier, an electric pressure cooker is the best solution. Delayed start times, quiet operation, and built-in timers make it simple to have dinner ready at just the right time. While stovetop variants can often cook a bit faster, electric pressure cookers still offer dramatically reduced cook times when compared to other cooking methods. As an added bonus, many electric pressure cookers offer additional cooking options, serving as slow cookers, air fryers, rice makers, and more. To learn more about multi-cookers, check out our Multi-Cooker Buying Guide.

Stovetop pressure cookers offer even shorter cook times than their electric counterparts. These shorter cook times are possible because stovetop pressure cookers are often capable of containing higher pressures, allowing the water inside to reach higher temperatures. Their durable, straightforward construction makes it possible for well cared for devices to last generations. And while older models could be as noisy as a train whistle, newer models are much quieter. However, it's important to keep a watchful eye on stovetop pressure cookers as they climb to your desired pressure. This minor inconvenience often outweighs the benefits they offer in terms of durability and pressure management.

Once you've decided between an electric or stovetop model, you'll need to figure out what size makes the most sense for you. Pressure cookers range from petite 2 quart containers to industrial size 20+ quart options. Most home models offer between 4 and 8 quarts, and a good rule of thumb is to think of each quart as a serving for a single person. Whatever size you end up choosing, it's important not to overfill your pressure cooker. Depending on what you're cooking, you should only ever fill ⅔ of the pot for solid foods, down to as little as ⅓ of the pot for dishes with pulses like lentils.

The most durable pressure cookers are made out of stainless steel. In comparison to aluminum, the next most common material, stainless steel is notably more durable. Many electric pressure cookers use aluminum covered with a non-stick coating. The smooth non-stick surface makes cleanup a breeze. However, you have to be careful not to scratch the coating when using metal utensils. Newer models may offer anodized aluminum with ceramic coatings, proving far more durable than older non-stick options.

While there may never be a "best pressure cooker," you should now have a general idea about which is best for you. At the very least, you should be able to answer our original questions, "What is a pressure cooker?" and, "How does a pressure cooker work?" As a refresher, a pressure cooker uses steam and a sealed lid to increase its internal pressure which increases the boiling temperature of the water within. The higher water temperature dramatically reduces cook times. Electric models allow you to input your desired temperature, pressure and/or time then walk away. Stovetop pressure cookers require a bit more attention but can often reach higher temperatures and offer greater durability. When selecting a size, think of each quart as a serving for one person. Take home your personal best pressure cooker today and get to cooking!