How many btu's are in a bic lighter?

A typical Bic lighter contains about 1.5 to 2 grams of butane, which translates to approximately 3,000 to 4,000 British thermal units (BTUs) of energy when fully ignited. This energy can vary slightly depending on the specific lighter and its fuel content. However, it's important to note that not all the energy is utilized in a single use, as the lighter is designed for intermittent use.