Hot Chile Peppers on the Scoville Scale

Know how hot that pepper is

Close up of red chili peppers on cutting board
Adam Gault / Getty Images

If you are not well-versed in the wide variety of peppers, you probably don't know the level of spice each type of chili pepper contains. Whether a jalapeno, habanero, or serrano, each has different degrees of heat, which is determined by how much capsaicin (a compound responsible for the pungency) the pepper contains. Luckily, this capsaicin can be measured in Scoville Heat Units, or SHU, on the Scoville Scale.

This chart lists the peppers by how may SHU are in each pepper, from the thousands for milder peppers all the way up the hundreds of thousands and even millions for the spiciest varieties.

The presence of capsaicinoids in chile peppers is an irritant, but it is common for people to experience pleasurable and even euphoriant effects from ingesting capsaicin. Fans of chiles attribute this to a pain-stimulated release of endorphins. A different reaction makes capsaicinoids useful as analgesics: applied topically, the heat of the chili gives relief to muscle pains and some forms of neuropathy.

How the Scale Works

The Scoville Heat Scale is a measuring tool developed by a pharmaceutical company employee named Wilbur Scoville in 1912. His original method was called the Scoville Organoleptic Test and used human tasters to evaluate how many parts of sugar water it takes to neutralize the heat. The pepper would be ground up and then mixed with the sugar water.

The testers would taste the pepper-water mixture, and the sugar water would then be increased until the pepper was no longer hot to the taster. The peppers would be given a number based on the number of times the dilution was added to mask the heat.

Unfortunately, this procedure was not very reliable and completely subjective.

 Nowadays, human tasters are spared and a new process called HPLC, or High-Performance Liquid Chromatography, measures the number of capsaicinoids (capsaicin) in parts per million the pepper contains. That number is then converted into Scoville Units (using an equivalent of 15 Scoville Units). 

Although the current method of measuring chili pepper heat is much more reliable than the previous technique, there is still room for variation. The conditions in which the pepper grows will affect the level of spice in the pepper; so if the same type of pepper was grown in different types of soil with varying amounts of sunlight, the amount of capsaicin will differ. There is also some question on the accuracy of the conversion of from HPLC units to SHU.

From Mild to Inedible

The Scoville Scale measures the heat level in all kinds of peppers, from sweet bell peppers and pimentos (which have almost no SHU) to the ghost pepper, which can hit above 2 million SHU. A few of the peppers on the high end of the scale are not for human consumption—they are just way too hot to eat. 

Even so, chili pepper aficionados are locked in intense rivalry to create the world's hottest pepper. Since 2011, when the competition began to heat up (pun intended), the title of hottest pepper has changed hands a number of times as new crosses and genetic mutations have emerged.

In 2013, the Carolina Reaper was named by the Guinness Book of World Records the world's hottest pepper, measured at 2,200,000 SHU. It's a cross between the Pakistani Naga and a Red ​Habanero.

Hot Pepper Scale in Scoville Units

This chart takes the SHU of different pepper varieties and then categorizes the peppers into heat ratings, with 0 being mildest and 10 representing the highest heat.

VarietyRatingHeat Level
Sweet Bells, Sweet Banana,  Pimento0Negligible Scoville Heat Units
 
Mexi-Bells, New Mexica, New Mexico, Anaheim, Big Jim, Peperonicini, Santa Fe Grande, El Paso, Cherry1100-1,000 Scoville Heat Units
Coronado, Mumex Big Jim, Sangria, Anaheim21,000-1,500 Scoville Heat Units
Pasilla, Mulato, Ancho, Poblano, Espanola, Pulla31,500-2,500 Scoville Heat Units
Hatch Green42,000-5,000 Scoville Heat Units
Rocotillo52,500-5,000 Scoville Heat Units
Yellow Wax, Serrano, Jalapeno, Guajillo, Mirasol65,000-15,000 Scoville Heat Units
Hidalgo, Puya, Hot Wax, Chipotle715,000-30,000 Scoville Heat Units
Chile De Arbol, Manzano830,000-50,000 Scoville Heat Units
Santaka, Pequin, Super Chile, Santaka, Cayenne, Tobasco, Aji, Jaloro950,000-100,000 Scoville Heat Units
Bohemian, Tabiche, Tepin, Haimen, Chiltepin, Thai, Yatsufusa10100,000-350,000 Scoville Heat Units
Red Savina Habanero, Chocolate Habanero, Indian Tezpur, Scotch Bonnet, Orange Habanero, Fatali, Devil Toung, Kumataka, Datili, Birds Eye, Jamaican Hot11350,000-855,000 Scoville Heat Units
Ghost Pepper (Bhut Jolokia, a.k.a. Naga Jolokia), Trinidad Moruga Scorpion12855,000-2,100,000 Scoville Heat Units