In 1912, Wilbur Scoville developed a method of ranking chiles. Scoville mixed ground chile in a simple syrup and had a panel of tasters taste the solutions. The ratio of simple syrup to chile where the tasters were unable to taste the chile spiciness was the rating given to the chile. For example, a serrano chile might need 8000 parts simple syrup to 1 part chile before you would be unable to taste the chile.
Type(Scoville) Rating 1-10
Hungarian Cherry Pepper 1-3
Aji Panca 1.5
New Mexico (NuMex Eclipse) 2- 3
New Mexico Miniatures 2-3
Guajillo 2-4
Mulato 2- 4
New Mexigo (red) 2-4
Aji Mirasol(2,500-5,000) 2.5
Chilhuacle Rojo 3
Ancho(1,000-2,000) 3-5
New Mexico (green) 3-5
Pasilla(1,000-2,000) 3-5
Cascabel 4
Chilhuacle Amarillo 4
Costeno Amarillo 4
Chihuacle Negro 4-5
Onza 4-5
Catarina 5
Chilcostle 5
Pasado 5
Pepperoncini 5
Chipotle(15,000 ) 5-6
Patzcuraro 5-6
Chiltepe 6
Mora 6
Pulla 6
Costeno 6-7
Pasilla De Oaxaca 6-7
Pico De Pajaro 6-7
Aji Amarillo 7-8
Morita 6.5
Tuxtla 7
Serrano Seco De Yucatan(5,000-15,000) 7
De Arbol(15,000-30,000 ) 7.5
Cayynne(30,000-50,000 ) 8
Tepin 8
Pequin(140,000 ) 8.5
Habanero 10
Type(Scoville) Rating 1-10
Bell pepper(0-100) 0
Hungarian sweet chili 0- 1
Sweet Purple pepper 0 -1
Pimento 1
Hungarian Cherry Pepper 1- 3
Anaheim (green) chili 2-3
Anaheim (red) chili 2- 3
Poblano (green or red) 3
Chawa 3-4
New Mexico (red) 3- 4
Chilaca 3-4
New Mexico (green) 3-5
De Agua (red or green) 4-5
Guero 4.5 - 6.5
Huachinano 5-6
Jalapeno(green) (2,500-5,000) 5.5
Jalapeno(red) (2,500-5,000) 5.5
Dutch (red) 6
Santa Fe Grande 6
Fiesta Fips 6-8
Korean 6-7
Fresno Red 6.5
Serrano (red or green) 7
Manzana 7-8
Peruvian (gr, yellow, red) 7-8
Rocotillo (red, green) 7-8
Thai (100,000-350,000) 7-8
Peter Pepper 7.5
Tepin 8
Brazilian Malagueta 9
Jamaican Hot 9
Tobasco (30,000-50,000) 9
Macho (green) 9-10
Macho (red) 9-10
Scotch Bonnet(100,000-350,000) 9-10
Habanero(200,000 to 300,000 ) 10
Naga jolokia (India) 10 plus ? 280000 up ?
(hottest chili - confirmed by Guinness World Records)