I have rash on my ankle that itches really bad?

Ankle rash. Ankle rashes can be caused by a wide variety of diseases, disorders and conditions, such as infection, inflammation, allergic reaction, eczema, insect bites, and autoimmune processes. For example, an acute ankle rash that appears suddenly may be caused by an allergic reaction or sensitivity to a particular substance, such as poison ivy. See you dermatologist for a diagnosis and treatment.
Could be dermatitis. If it is long standing it could be eczematous eruption or a fungal infection, if there is a skin rash. Needs to be evaluated by dermatologist.