LDL Cholesterol Calculator is a free iPhone app developed by The Johns Hopkins University's Ciccarone Center for the Prevention of Cardiovascular Disease. It automates the calculation of LDL cholesterol using a method published in the Journal of the American Medical Association. By inputting total cholesterol, HDL cholesterol, and triglyceride levels, the app provides personalized LDL cholesterol calculations, moving away from the traditional fixed factor approach. Endorsed by major clinical guidelines like the American Heart Association, the app's results aim to guide rather than replace clinical judgment. Developed by Dr. Seth S. Martin and collaborators, users can rely on the app's accuracy and credibility for informed discussions with healthcare providers.