Carolina Reaper is officially considered to be the hottest chilli pepper in the world. It measures 2,200,000 SHU, a measure used to calculate spiciness. Pepper X is two times as hot as the Carolina Reaper, which would make it the hottest pepper in the world with a Scoville scale of 3.18 million units, but this remains unconfirmed by Guinness World Records as of 2021. But Carolina Reaper is officially confirmed with a Guinness-submitted 1,641,183 Scoville Heat Units (previously submitted as 1,569,383 SHU average and recently measured peak levels of over 2,200,000 SHU). Until Pepper X is officially confirmed, Carolina Reaper will be the hottest chilli pepper in the world.