The bhut jolokia pepper, also known as the ghost pepper, is approximately 400 times hotter than Tabasco sauce with a Scoville-scale rating of 1 million units. In 2007, it was certified by the Guinness Book of World Records as the world's hottest pepper, but has since been surpassed.
In 2013, Guinness certified the Carolina Reaper as the world's hottest pepper, with a Scoville rating of 2.2 million units. The second-hottest pepper is the Trinidad or Moruga Scorpion, coming in at 2 million units. As of 2014, the ghost pepper remains in third place.
While the Carolina Reaper is the hottest naturally grown pepper, there are extracts of pure capsaicin that reach Scoville ratings of more than 10 million units, making them much hotter than any naturally grown pepper in the world.