What are BTUs?

What are BTUs?

BTU, or British Thermal Unit, is a measurement of the total heat output and fuel consumption per hour of all grill burners. Think of BTU as a fuel efficiency rating not how hot your grill will get. Higher BTU doesn't mean a hotter grill. The most important features to look for are even heat and the ability to sear.

what is a btu?

A British Thermal Unit (BTU) is a standard unit of energy used in the United States and sometimes in the U.K. On the most basic level, it’s the amount of thermal energy needed to raise the temperature of one pound of water by one degree, specifically from 39°F to 40°F.

For our purposes, BTU is a measurement of thermal output of a heating or cooling appliance. For example, in the air conditioning industry, BTUs refer to how much heat the air conditioner can remove from the surrounding air. In the grilling industry, BTUs are a measurement of how much heat a grill generates at its maximum output.

If you think of BTUs like your car’s fuel efficiency or MPG (miles per gallon), BTUs measure your grill’s fuel efficiency or OPB (output per burner) as well as all the burners combined. Since the number of BTUs for all burners combined is a bigger, more impressive number, it’s the number that’s usually promoted to sell grills. It may seem like anything with a high BTU rating (grills, fireplaces and heating equipment) will be hotter and therefore better. Though BTU rating does influence temperature, it’s far from the only thing that determines how hot your grill can get.

For instance, airflow is an important factor in reaching and maintaining high temps. Even if a grill has the highest BTU rating, if it doesn’t have good airflow, it won’t necessarily be hotter. In fact, it will very likely have hot and cold spots.

primary cooking area

The optimal number of BTUs for your grill is determined by the cooking area. To get the actual number of BTUs-per-square-inch for your grill, divide the main burner BTU total by the size of the primary cooking area. When purchasing a standard convective grill, we recommend 75 to 100 BTUs-per-square-inch. For an TRU-Infrared™ grill, 50 to 80 BTUs will be all you need.

Where you get the best of both worlds (higher heat and fuel efficiency) is with Infrared Burners. The technology in these burners allow for both super-hot temperatures and great fuel efficiency.  While the burners of a standard gas grill heat the cooking chamber by convection, an infrared grill converts the heat of its burners to radiant energy by limiting airflow. This allows the chamber to heat up fast and maintain a high temperature, making this type of grill one of the most efficient on the market.


Char-Broil® TRU-Infrared™ gas grills don’t need as high an output of BTUs as traditional convective grills. TRU-Infrared emitters efficiently manage and distribute the heat throughout the firebox, requiring less BTUs. This heat is quickly and efficiently transferred directly to your food, searing food quickly, locking in juices and using less fuel.

Higher BTUs don’t necessarily mean a hotter grill. In fact, higher BTUs may mean that energy is being wasted to achieve and maintain temperatures like you would with an efficient firebox.


Today's grills are more efficient and don't need as much BTU output as they once did. When looking for a gas grill, look for solid construction and check out how well the lid fits the body. If it fits snugly and the grill's components are heavy, it will likely heat up quickly and maintain cooking temps.


Grills with extremely high BTU-per-square-inch ratings may be calculated in a deceptive manner or have inferior design and construction. Grills with BTU ranges that are lower than standard recommendations will likely be slow to preheat and heat back up after opening and closing the lid to tend to your food.

When you’re looking for your next gas grill, don’t let the BTU rating be the most important factor. Should you consider BTUs as one of the factors? Absolutely. Consider the total BTUs, the primary cooking area and the number of BTUs-per-square-inch. But don’t let that be the deciding factor in your purchase. To make an informed decision, look at all of the grill’s features, including the warranty. And think of the BTU number as a fuel efficiency rating not how much heat the grill produces.

Suggested for this How-to
Comments & Questions