One in five Americans is affected by skin cancer, making it the most common cancer in the United States. Excluding non-melanoma skin cancer (NMSC), melanoma is the fifth most common cancer, and it is projected that over 100 000 new cases of melanoma will be diagnosed in the United States by the end of 2020. Although melanoma accounts for only 1% of all skin cancers, it causes a majority of deaths and it is expected that almost 7000 people will die from melanoma by the end of the year. [1] Each year, over 5.4 million cases of NMSC are treated in the United States in over 3.3 million people. [2] Despite continuous efforts to promote public awareness about sunburn and skin cancer risk, sunburn remains highly prevalent among American adult populations (Figure 1). Surveys from the Centers for Disease Control (CDC) show that sunburn prevalence remains high, with 50.1% of all American adults and 65.6% of whites aged 18-29 years reporting at least one sunburn every year. [3] Sunburn usually diminishes several days after exposure; however, repeated sunburn causes cumulative genetic and epigenetic damage in skin cells. Although sunburn is a well-established risk factor in skin carcinogenesis, there are often decades-long delays between sunburn events and visible skin tumor lesions (Figure 2). Sunburn-induced molecular changes can persist for years to decades in sun-exposed pre-malignant skin, which can lead to malignant transformation over time. While conventional skin cancer screening methods including dermoscopy are useful in tumor detection, they often fail to detect tumors at early stages due to their inability to detect such cancer-causing molecular alterations prior to visible tumor formation. [4-6] Currently, measurement of skin sun damage relies on the use of minimal erythema dose (MED), which describes the amount of ultraviolent radiation (UVR) that produces visible skin