Ferrostatin-1 (Fer-1) is a potent inhibitor of ferroptosis, a regulated form of cell death driven by iron-dependent lipid peroxidation. It is widely used in research to study the mechanisms and implications of ferroptosis in various disease models. One of its primary applications is in neurodegenerative disease research, where it helps protect neurons from oxidative damage in models of Alzheimer’s, Parkinson’s, and Huntington’s diseases. By preventing lipid peroxidation, Fer-1 maintains cellular integrity and function under oxidative stress. It is also applied in ischemia-reperfusion injury studies, particularly in the heart and brain, where it reduces tissue damage following stroke or myocardial infarction. Its ability to cross cell membranes makes it effective in both in vitro and in vivo systems. In cancer research, Fer-1 is used as a tool compound to distinguish ferroptosis from other cell death pathways, helping to evaluate the role of ferroptosis in tumor suppression or therapy resistance. Additionally, Fer-1 has shown protective effects in kidney injury models, especially in acute kidney injury induced by toxins or oxidative stress, highlighting its potential for studying organ protection strategies. Due to its specificity and efficacy, Fer-1 remains a key pharmacological agent for probing ferroptosis in biomedical research.