Question: how spicy are guajillo chiles?
Answer: The guajillo pepper is considered a mild to medium heat level chili, measuring from 2,500 to 5,000 Scoville Heat Units on the Scoville Scale. Compare that to a jalapeno pepper, which ranges from 2,500 to 8,000 SHU, and it can be roughly equivalent to the jalapeno in heat.