Skin whitening, also known as skin lightening and skin bleaching, is the practice of using chemical substances in an  attempt to lighten the skin or provide an even skin color by reducing the melanin concentration in the skin.

Several chemicals have been shown to be effective in skin whitening, while some have proven to be toxic or have questionable safety profiles. This includes mercury compounds which may cause neurological problems and kidney problems. In a number of African countries, between 25 and 80% of women regularly use skin whitening products. In Asia, this number is around 40%.In India, specifically, over half of skin care products are sold to whiten skin. Efforts to lighten the skin date back to at least the 1500s in Asia.

Historian Evelyn Nakano Glenn attributes sensitivities to skin tone among African Americans to the history of slavery. Lighter-skinned African Americans were perceived to be more intelligent and skilled than dark-skinned African Americans, who were relegated to more physically taxing, manual labor. Studies have additionally linked paler skin to achieving various forms of social standing and mobility. A study by Kelly Lewis and her colleagues found that, in Tanzania, residents choose to bleach their skin to appear more European and impress peers and potential partners. Both advertisements and consumers have suggested that whiter skin can enhance individual sexual attractiveness.

Sociologist Margaret Hunter noted the influence of mass-marketing and celebrity culture emphasizing whiteness as an ideal of beauty. A study by Itisha Nagar also revealed that lighter skin tones in both men and women in India improved their prospects for marriage. Skin whitening is a major issue throughout Asia. In South Korea, light skin is considered an ideal of beauty and most South Koreans believe that having paler skin is the only way to look beautiful. In South Korea, skin whitening is a multi-billion-dollar industry. The K-pop and K-drama industries are saturated with fair-skinned celebrities, some of whom serve as brand ambassadors and beauty ideals. The trend of having fairer skin can be traced back to several centuries, where white skin was a sign of being high in the social hierarchy since those who were wealthier did not have to work outside in the fields.

The increasing popularity of K-pop and K-beauty has driven the skin whitening trend elsewhere in Asia, especially in poorer countries like Thailand, where many have begun to use unsafe skin-whitening products. Other motivations for skin whitening include desiring softer skin and wanting to conceal discolorations arising from pimples, rashes, or chronic skin conditions. Individuals with depigmenting conditions such as vitiligo have also been known to lighten their skin to achieve an even skin tone. According to local analytics in Asian countries, people with white skin are more likely to get more opportunities over brown or brownish skin. It is advised to use natural ways to get clear and fair skin instead of using chemicals.