The Heat Scale of Mexican Chiles, With US Equivalents

From poblano to habanero in Scoville order, with the American peppers that come closest, what each chile actually tastes like, and how to dial heat down.

Heat is the first thing Americans ask about a Mexican chile and the least useful thing to know about it. A guajillo and a chile de árbol are worlds apart in flavor and only one step apart on anything a jar label would tell you. Still, you need a map, so here is one — ordered by heat, with what each chile is for and the US pepper that sits closest to it.

The numbers are Scoville heat units, the standard capsaicin measure. Treat them as ranges, not readings: the same variety grown in two fields can differ by a factor of three, and the dried version of a fresh chile is always more concentrated by weight. For reference, a jalapeño you buy in an American supermarket is usually at the mild end of its own range, because that is what sells.

The scale, mild to brutal

Chile	Scoville (approx.)	Tastes like	Closest US pepper
Poblano (fresh)	1,000–2,000	Green, vegetal, faintly bitter skin	Large green bell pepper plus a pinch of cayenne
Ancho (dried poblano)	1,000–2,000	Raisin, prune, cocoa	No real equivalent; sweet paprika gets the color only
Mulato (dried)	2,500–3,000	Darker than ancho, licorice and dried fig	None
Guajillo (dried)	2,500–5,000	Bright, tangy, berry and tea	New Mexico red chile, widely sold in the Southwest
Pasilla (dried)	1,000–4,000	Herbal, cocoa, mushroom	None
Jalapeño (fresh)	2,500–8,000	Grassy, juicy, sharp	Itself — it is an American supermarket staple
Chipotle (smoked jalapeño)	5,000–10,000	Smoke, leather, sweetness in adobo	Smoked paprika plus jalapeño, imperfectly
Serrano (fresh)	10,000–23,000	Cleaner and hotter than jalapeño, less juicy	Fresno or a hot jalapeño
Chile de árbol (dried)	15,000–30,000	Straight heat, nutty when toasted	Cayenne
Piquín / chiltepín	50,000–100,000	Fast, sharp, fades quickly	Thai bird chile
Habanero	100,000–350,000	Apricot, tropical fruit, long burn	Scotch bonnet

What the scale does not tell you

Two chiles at the same heat level can do opposite things to a dish. Guajillo is the backbone of a red salsa because it is acidic and bright; ancho at the same heat makes that salsa taste like a dessert sauce. Pasilla is what gives a dark mole its earthiness, and no amount of cayenne will stand in for it. When a recipe names a dried chile, it is naming a flavor, and the heat is incidental.

Dried chiles also need toasting. Thirty seconds a side on a dry skillet until they smell of toast and go pliable, then a soak in hot water for twenty minutes. Toast them until they smoke and the whole sauce turns bitter — that is the most common mistake in American kitchens working from a recipe written for cooks who already knew.

Fresh, dried and smoked are three different ingredients

The same plant shows up on the shelf in three forms, and they are not interchangeable. A fresh poblano is a vegetable you char and peel and stuff. Dried, that poblano is an ancho, and it becomes the sweet, dark base of an adobo. A fresh jalapeño is a crunchy, grassy condiment; smoked and dried, it is a chipotle, and it brings smoke to everything it touches. Nothing on the label tells you this, so recipes assume it.

This is also where canned products earn their place. Chipotles in adobo are genuinely useful and have no good homemade substitute in a weeknight kitchen: the can gives you smoke, acid, sweetness and heat in one spoonful. Pickled jalapeños in escabeche are the same story. Canned whole green chiles, on the other hand, are a Southwestern product closer to a mild Hatch chile than to anything Mexican.

How much to use

For a table salsa for four, a useful starting point is four to six dried guajillos plus one or two chiles de árbol, which lands mild to medium. One more árbol takes it to clearly hot; four takes it somewhere most guests will not follow. For a fresh salsa, one serrano per two tomatillos is medium and one per tomatillo is hot. Build up rather than down: you can always add toasted chile to a blender, and you cannot take it out.

Write down what you used the first few times. Heat tolerance is personal and chiles vary batch to batch, so your own notes will beat any Scoville chart within a month of cooking.

Dialing the heat down without losing the dish

Capsaicin lives mostly in the seeds and the white pith. Scraping both out of a fresh chile takes a serious amount of heat off while leaving the flavor, which is why a stuffed poblano is mild and a salsa made with the same chile can bite. For dried chiles, discard the soaking water if the batch came out hot: a good part of the capsaicin leaches into it.

In a finished dish, fat and dairy are what rescue you. Crema, queso fresco, avocado and a corn tortilla all blunt heat; water and beer do not, and carbonation makes it worse. Sugar helps a little. Lime helps the perception without changing the heat.

If you want to taste the difference between chiles rather than read about it, make Red Salsa with guajillo and then again with ancho, and keep notes. Our Habanero Salsa is the far end of the scale, and Chipotle Salsa is the one that converts people who think they do not like heat.

One last practical note on storage, because it affects heat more than people expect. Whole dried chiles keep their flavor for about a year in a sealed bag away from light, and they lose aroma long before they lose heat — which is how a year-old guajillo ends up tasting like nothing but warmth. Ground chile powders fade faster still, in three or four months. Buy whole, buy often, and grind what you need.

Where the chiles are

Whole dried chiles are a Mexican grocery item more than a supermarket one. In our US directory, 237 of the 536 active stores are neighborhood groceries, mercados or meat markets, and those are where you find guajillo, ancho and pasilla sold loose by weight rather than in three-chile cellophane bags. The 268 full-line supermarkets in the directory carry them in larger bags, often in a dedicated chile section.

A handful of examples: La Michoacana Meat Market (Houston), Mendoza's Mexican Mercado (Seattle), Carniceria El Paisano (Seattle), La Michoacana Meat Market (Houston), El Mercado Latino (Seattle), Morelia Supermarket (Chicago). The full list is in our US store directory.