What miracles did Saint Cecilia perform to become a saint?

At the time Saint Cecilia was martyred, no miracles were required for a person to be declared a saint. Cecilia was declared a saint by the local Christians with the approval of the bishop based on her life of heroic virtue and martyrdom.

We have no record of any miracles worked by Our Lord through the intercession of St. Cecilia. However, when her body was exhumed in the 16th century, it was incorrupt and looked as fresh as on the day she died 1400 years earlier.