The International Food Information Council recommends a daily caffeine intake of 300 mg, while the FDA recommends 400 mg, but just one 12-ounce cup of Black Insomnia brew contains 702 mg of caffeine, which will definitely keep you up at night and may even cause some health problems.
Black Insomnia Coffee was founded in 2016 by South African coffee lover Sean Kristafor. From the very beginning, his goal was to create the strongest coffee in the world, and he managed to do it by using the stronger Robusta variety, instead of the more aromatic Arabica. The secret to its high caffeine content is apparently in the way that the coffee beans are roasted, but Kristafor is obviously not interested in revealing the process. He only says that they can make it considerably stronger, and actually had to dial it down a bit for the commercial version, just so it was safe to consume.