Acne is one of the most common skin diseases and usually affects younger people; it significantly impacts quality of life1. Many people worldwide use the internet to search for health information, especially adolescents, who prefer the internet as their primary source of health information2. Therefore, there is potential demand for internet-based information about acne. Accordingly, we designed a web-based study using Google Trends (http://www.google.com/trends/) to compare relative search volumes using keywords for acne and other diseases including eczema, alopecia, psoriasis, and diabetes. The languages of the keywords were English and Spanish, which are representative languages of regions where Google is the most popular search engine. The keywords for acne were "acne", "pimple", "pimples", "zit", "zits", "grano", and "granos". The keywords for eczema were "eczema", "eccema", "dermatitis", and "cutitis". The keywords for alopecia were "alopecia", "hair loss", "baldness", "calvicie", and "calvez". The keyword for psoriasis was "psoriasis". The keywords for diabetes were "diabetes" and "glucosuria". The relative averages of the search volume of each disease and monthly relative search volumes worldwide from January 2004 to May 2013 are shown in Fig. 1. The relative search volume of acne was greater than that of other dermatologic diseases and has increased gradually since 2008. However, the relative average search volume of acne was less than that of diabetes, but in recent years, its search volume has exceeded that of diabetes. As shown in Fig. 2, in past 90 days, the relative average of search volume of acne was greater than that of diabetes. Line graphs followed a periodic trend in weekly intervals. On weekends, the search volume of acne peaked while that of diabetes showed a lower peak. Google Trends provides the relative volume and geographic distribution of Google Web searches; these data are convenient, accessible, representative of large populations, and can be used in various medical fields3,4,5. The present results show that acne is relatively more searched for than other dermatologic diseases. As acne occurs mostly in young people, who use the internet as a primary source of health information, it might be more searched for on the internet than other dermatologic diseases. The search volume of acne has increased gradually since 2008. Furthermore, in recent years, acne has become more searched for than diabetes. This increasing trend may be attributable to the impact of the widespread use of smart phones by young people. Young people are relatively busy on weekdays and like to search for health information on the internet. Therefore, unlike diabetes, the search volume of acne may peak during weekends. A limitation of this report is that only Google Trends was used to compare relative search volumes on the internet despite the existence of other search engines. Although there is strong interest in acne, a substantial amount of myths, incorrect information, and unconventional home remedies are present on the internet6. Accordingly, dermatologists should be aware of the strong interest in acne on the internet and try to supply accurate information online as well as in clinics.