Introduction. This thesis aims to investigate user participation in two selected music websites, The Metal Archives (also known as Metal-Archives or MA) and Discogs, as well as gather knowledge about how their databases and web interfaces are designed. Music genres are often associated with a culture or subculture. We wanted to investigate how the subcultures of metal music fans and record collecting has made an impact in these online archives, since the users who contribute to the archives are the ones who drive the archives forward. Method. To answer our research questions we described the designs of the websites themselves, as well as conducted surveys and one interview. Our survey material comes from user responses to two separate Google Forms surveys. The interview is a qualitative semi-structured interview conducted via e-mail with a policy expert from The Metal Archives. In addition to this, we supplemented it with a summary of an earlier interview with Discogs founder Kevin Lewandowsky. Qualitative method was used for analysis of both surveys and the interviews. Results. Both websites function as participatory archives since the user contributions are voluntary. Many who contribute do so out of a “Love for the culture”. While both user communities share a love for music, Discogs also focuses on its users selling physical records. Respondents from the surveys show an altruistic motivation for participating. To them, sharing contributions with others in the community feels important. Conclusion. Regarding website design, we found that both sites employ point systems as a motivating factor to ensure further user contributions. When it comes to user participation, both sites have active communities and can be seen as examples of crowdfunding. In the case of Metal-Archives the users showed a certain affect, passionately contributing data for its own sake. While both websites function as “Community Archives”, the culture differs. Metal-Archives is more elitist in nature and subcultural while Discogs aims to catalogue music from any genre. Furthermore, the search systems differ in that Metal-Archives is centred around finding bands while Discogs uses complex hyperlinking derived from the culture of vinyl record collecting. The thesis concludes that these two study objects show an example of community and the contributions of passionate fans online, as well as how the amount of information about music can benefit future research in music.  This is a two years master’s thesis in Archival Science.