How many red pepper flakes equals jalapeno pepper?

The heat of jalapeño peppers typically ranges from 2,500 to 8,000 Scoville Heat Units (SHU), while red pepper flakes usually measure around 30,000 to 50,000 SHU. As a general guideline, if a recipe calls for one jalapeño pepper, you can substitute approximately 1/4 to 1/2 teaspoon of red pepper flakes, depending on your heat preference. Adjust according to taste, as individual spice tolerances can vary significantly.