Perhaps the first thing to consider is the overall capacity of your chosen electric kettle. Most kettles list their capacity in liters, since they’re more popular in Europe, but some feature cup measurements, too. Most kettles fit around one-and-a-half to two liters, but you can find smaller options for compact kitchens. One liter is approximately four eight-ounce cups but bear in mind that your chosen drinking vessel may be larger than this. A window with measurement markings on the side of the kettle lets you see how much water is inside.