Gas Grill Buying Guide: Size, BTU, Grates and Build Quality

Shop in this order, because each step narrows the field before price starts pulling you around:

1. Primary cooking area. Size to the number of people you usually feed, not the biggest party you host once a year.
2. Cookbox and lid. Cast aluminum and thick stainless hold heat and do not rust through. Thin painted steel is the first part to fail on cheap grills.
3. Grates. Heavy cast iron or thick stainless rods sear better and last longer than thin stamped grates.
4. Burners and heat spreaders. Stainless or cast burners with a design that sheds grease, plus bars or plates that cover the burners completely.
5. Fuel. Propane for flexibility, natural gas if you have a line and cook often.
6. Warranty and parts. Long, component-by-component coverage and a parts catalog you can actually order from.
7. Extras last. Side burners, infrared sear burners and rotisseries are worth money only if you will use them.

Most people overbuy burners and underbuy build quality. A three-burner grill with a heavy cookbox, like the Weber Spirit E-325, will cook more evenly than a thin five-burner grill that costs the same.

Primary cooking area is the grate directly over the burners, where food actually grills. Total cooking area adds the warming rack above it, and sometimes the side burner. Marketing copy leads with the total because it is the bigger number. A grill listed at 780 sq in total may have 570 sq in of primary grate, which is the case for the Broil King Baron 520 Pro. Always size from primary area. Plan about 80 sq in of primary grate per person for a full meal of mains and sides, and check your number with the grill size calculator or the grill size for a family of 4 page.

BTU (British thermal unit) is the fuel a burner consumes per hour, not the heat that reaches your steak. A higher number means the grill burns more gas, and it says nothing about how much of that heat escapes out the back vents. The old rule of 80 to 100 BTU per square inch of primary grate is a rough floor, not a quality score. Heat retention comes from a heavy cookbox, a lid that seals, heavy grates and heat plates that spread the flame evenly. The table below uses published specs to show how similar the ratios really are across very different price points.

Cast iron holds the most heat and leaves the darkest sear marks, but it rusts if the coating chips or it sits wet. Porcelain-enameled cast iron, used on the Weber Spirit and Genesis, adds a glassy coating that resists rust until it chips, so use a bristle-free brush and avoid banging the grates. Stainless steel grates are lower maintenance and do not rust in normal use; what matters is thickness. Heavy stainless rods, such as the 7.5 mm grids on the Napoleon Built-In 500 or the 9 mm wave grids on the Napoleon Built-In 700, store enough heat to sear. Thin stainless wire grates do not.

• Choose cast iron if you want maximum sear and do not mind oiling grates and storing the grill covered.
• Choose heavy stainless if the grill lives uncovered, you live near salt air, or you want the least upkeep.
• Skip thin stamped steel on any grill you expect to keep more than a few seasons.

A side burner is a stovetop-style burner on the shelf for sauces, beans, corn or a pot of oil. It is worth paying for if you cook whole meals outside; if you mostly grill burgers and bring sides from the kitchen, it becomes an expensive shelf. The Weber Genesis E-435 and Charbroil Amplifire 4-Burner include one.

A sear burner is a high-output zone for crusting steaks. Some grills get there with boosted conventional burners, like the Weber Spirit E-325's Boost Burners that Weber says add 40 percent more power to the sear zone. Others use a ceramic infrared burner: the Napoleon Prestige 500 RSIB has an infrared side burner Napoleon says reaches 1800 F in 30 seconds, and the Broil King Regal S 690 Pro IR lists one rated to 1700 F. A rear rotisserie burner is only worth it if you will actually roast chickens and roasts on a spit. For a flat-top alternative to a side burner, compare the griddle vs gas grill page.

Buy the fuel version your patio can actually use, because most cart grills cannot be converted after purchase. Propane holds about 21,548 BTU per pound, so a full 20 lb tank stores roughly 431,000 BTU. Divide that by the BTU per hour you burn to estimate cooking time: a grill burning 30,000 BTU per hour on high empties a tank in about 14 hours, and in about 29 hours at half throttle. Keep a spare, like the Flame King 20 lb tank with gauge, and check levels by weight with a propane tank scale.

Natural gas never runs out and costs less per BTU in many areas, but the grill must be ordered as a natural gas model, like the Weber Spirit E-325 Gas Grill (Natural Gas) or Broil King Regal S 420 Pro Gas Grill (Natural Gas), and the line must be run by a licensed plumber or gas fitter, usually with a permit. Only convert fuels with the manufacturer's approved kit where one exists. The full cost and convenience breakdown is on propane vs natural gas grill, and run times for any tank are in the propane tank runtime calculator.

You can judge most of a grill in five minutes at the store, or from the parts diagram in the owner manual online:

• Cookbox: cast aluminum or heavy stainless. Weber lists a cast-aluminum cook box on the Spirit E-210 and E-325; Broil King uses a stainless cookbox with cast aluminum end caps on the Regal S line. Painted thin steel will eventually rust through.
• Lid: it should close with a solid sound and not rock. Double-lined hoods, like the Bull Outlaw's, hold heat in wind.
• Grates: lift one. Heavy is good.
• Burners: stainless or cast, with a design that sheds drippings. Look for flame tamers, bars or plates that fully shield them.
• Grease path: a funnel or tray you can reach from the front without moving the grill.
• Frame and casters: give the cart a push. Racking or wobble gets worse with age and weather.
• Certification: look for a CSA or ETL listing for the fuel type.
• Parts: search the model number plus "replacement burner" before you buy. Brands like Weber, Broil King and Napoleon keep parts available for years.

Warranty length is the maker telling you how long it expects the grill to survive, so read the component breakdown, not the headline. Many "lifetime" warranties cover only the cookbox, while burners, igniters and grates carry much shorter terms. Registration is often required. The figures below are from catalog listings; confirm current terms with the manufacturer before you buy.

Below about $400, grills are built to a price and usually last a few seasons; they are fine for occasional use. Between $500 and $900 you get the first grills built around cast aluminum or heavy cookboxes and long warranties, which is the sweet spot for most families. From about $1,100 to $2,000 you are buying capacity, stainless construction and features like infrared burners and rotisseries. Above that, you are paying for flagship finishes such as the Weber Summit FS38 E, or for a built-in grill for an island. The two price-capped roundups are gas grills under $500 and gas grills under $1,000.

Budget about $100 to $150 for the gear that protects the grill and the cook. A bristle-free brush like the GRILLART 18 in. Bristle-Free Grill Brush and Scraper removes the risk of loose wire bristles ending up in food. An TempPro TempSwift 0.5 Sec Instant-Read Meat Thermometer does more for results than extra BTU. A fitted cover, such as the Weber Premium Grill Cover for Spirit Gas Grills for Spirit models or the universal Unicook 58 in. Heavy-Duty Grill Cover, keeps pollen and rain out of the burners. A grill mat protects a wood or composite deck from grease. The full list is in best grill accessories, and a complete starter kit is laid out in the intermediate outdoor cooking setup. Smokers and pellet grills are a different category; SmokerCalc covers those.