A cooktop is essentially a range, minus the oven. What it lacks in functionality it makes up for in flexibility, at least in terms of kitchen design and layout. Cooktops can be installed anywhere ranges can; unlike ranges, cooktops can be built into kitchen islands, freeing up counter space, giving you more room to maneuver and making cooking a social activity. But you'll pay for that convenience -- you can easily spend $1,000 or more on a cooktop and still need to buy a separate wall oven in order to bake.
Like ranges, cooktops come in both gas and electric models. In general, reviewers say electric cooktops heat up faster and better maintain a consistent low heat. However, many cooks prefer the precision of a gas cooktop, which allows them to adjust the flame by sight. And natural gas generally costs less than electricity, making gas cooktops cheaper to operate over the long term. But choosing between gas and electric cooktops, experts say, is largely a matter of personal preference.
Gas cooktops typically have four or five burners with at least one high-powered burner (for tasks such as boiling water) and one smaller burner (for simmering or keeping food warm). The heat output of each individual burner is measured in British thermal units (Btu). Most gas cooktops have sealed (one-piece) burners, which are easier to keep clean than unsealed models because there's no burner well for crumbs to fall through. Many gas cooktops -- even some basic models -- have continuous grates that fit together seamlessly so you can slide heavy pots and pans between burners. Gas cooktops are available in both 36- and 30-inch models.
Smoothtops -- by far the most popular type of electric cooktop -- have radiant burners under a layer of ceramic glass. They are easy to clean, although some manufacturers recommend using gentle cleansers to avoid damaging the cooktop's delicate surface. While most electric cooktops measure 30 inches wide, some 36-inch models are also available. Most electric smoothtops have four burners of various sizes to accommodate different pots and pans. Some cooktops can detect pan size and will automatically adjust the burner to fit the pan. Burners of different sizes also tend to vary in power level, which is expressed in watts.
In the past several years, induction cooktops have become more common. These models have smooth glass surfaces, too, but they use electromagnetic elements, which heat the pan directly rather than transferring heat from a radiant burner to the pan bottom. Cookware must be magnetic -- made of stainless steel or cast iron -- in order for an induction cooktop to work; glass and ceramic cookware won't do. Popular Mechanics magazine does an excellent job of explaining in detail how induction cooktops work.
In professional tests, induction cooktops excel at quickly boiling water and holding a precise simmer. Because the induction process heats the cookware material itself -- rather than applying heat with an exposed burner or cooking element -- these cooktops stay relatively cool to the touch. The big downside is cost; induction cooktops start at about $1,200. You'll also need to invest in magnetic cookware made from stainless steel or cast iron; other types of cookware (ceramic, glass) won't work.
Electric cooktops with old-fashioned coil burners still exist, though only at the low end of the price spectrum. These are harder to clean than smoothtop models, because food can easily fall below the burners, but they are easier (and cheaper) to repair if they break. And unlike smoothtops, you don't have to worry about scratching or breaking the unit's surface.
In terms of efficiency, there isn't a huge difference between gas and electric cooktops, according to the American Council for an Energy-Efficient Economy. In general, gas is cheaper than electricity. However, cooktops don't use a lot of energy to begin with, so overall, experts say the difference is negligible. Gas and electric cooktops also have similar rates of repair, according to one owner survey. Nearly all cooktops come with a standard one-year warranty, although some manufacturers cover the heating elements or surfaces for longer periods.
Overall, we found ConsumerReports.org to be the best source for cooktop reviews. Editors report test results for more than 40 electric and gas cooktops on their website, including several induction models. Cooktops are tested on their ability to boil water, simmer tomato sauce and melt chocolate without scorching. However, rankings and test results are available only to subscribers.
To gain an overall picture of each brand's performance and reliability, we consulted J.D. Power and Associates' 2012 survey on kitchen appliances. For the survey, more than 3,800 owners rated their large kitchen appliances -- including cooktops, wall ovens and ranges -- on factors such as performance, styling and price. Individual cooktops aren't rated, but the information is useful for gauging overall brand satisfaction for these appliances.
Cooktops do not receive nearly as many owner-written reviews as most other appliances, but we were able to collect a smattering of opinions from sites such as AJMadison.com, HomeDepot.com and Lowes.com. Sites that aggregate user reviews, such as Buzzillions.com and Google Shopping, provide a broad overview of owner opinions from different sources.