In the marketing industry, endorsements are a widely used promotional strategy to increase the appeal and credibility of a product. According to previous research conducted by (Hanaya et al., 2024), endorsements leverage the significant influence of public figures or celebrities to support a product, either by recommending its use or writing positive reviews to encourage people to buy it. The main goal is to attract customers who are interested in the character that is the center of attention.

Celebrities as endorsers are very important to ensure that the message conveyed attracts attention (Wihayati, 2017). In advertisements involving celebrities, the presence of these famous figures can increase the appeal of the advertisement and help convey the product message more effectively. Ultimately, this can have an impact on consumers' views and interest in the promoted product.

According to previous research by (Evanthi et al., 2024), celebrity endorsements are a marketing approach that involves celebrities with large numbers of followers on social media to promote products. Celebrities with endorsements on social media platforms are considered effective because they can reach customers more directly and personally and provide recommendations or endorsements that can influence their decision to purchase a product.

Currently, social media has changed the way teenagers interact, express themselves, and obtain information. Instagram and similar platforms are not only communication tools but also play a role in shaping the social habits, identities, and consumption patterns of young people. This change marks a major shift in the world of communication and popular culture, where social media has now become a place to find meaning and build identity.

Social media not only plays an important role in modern society, but also functions as a platform for advertising and sharing data, information, and expressions. Social media is very effective for marketing because of its large number of users, which allows brands to reach a larger audience.

Social media as an online advertising channel is an effective way to quickly introduce goods or services to customers with a wider reach than conventional media. Additionally, advertising on social media is more affordable and practical, which is why many companies in Indonesia use this platform to promote their products or services. This supports the opinion of Kotler and Keller, who state that social media is very important for marketing (Aprilianti & Hasbi, 2024).

Businesses can use various methods to market their products, one of which is by using digital and online platforms such as Instagram for promotion. According to Kotler and Amstrong, the fastest growing type of direct marketing is digital or online marketing. Endorsement is a digital strategy that is widely used by businesses today (Atala & Komsiah, 2023).

Instagram is a visual social media platform created by Kevin Systrom and Mike Krieger and launched in 2010. This free digital application for various media is intended for smartphone users. With its main feature, users can upload and distribute photos and videos to their followers and community of friends.

Instagram has an advantage in digital social interaction because it allows users to explore, give appreciation through likes and comments on every content displayed on the platform (Watajdid et al., 2021)

Tasya Farasya is a beauty influencer with 7,055,130 followers on Instagram. By endorsing Emina cosmetics products aimed at teenagers, she has the opportunity to see how influencers can build relationships between brands and teenage demographics.

The purpose of this study is to gain a deeper understanding of field phenomena. Moleong (2007) states that qualitative research is a type of research that uses descriptive data to explain social or human phenomena in depth. Meanwhile, Creswell (2014) states that research that produces descriptive data in the form of written or spoken words from people and their observed behavior. Qualitative researchers seek to understand the experiences, perspectives, and actions of research subjects in the context of their real lives.

Researchers selected informants based on criteria relevant to the research objectives. The research informants were adolescents who met the following criteria:

For research purposes, purposive sampling was used to select informants who were considered to have sufficient information to answer the research questions (Sugiyono, 2012).

This study uses triangulation of sources and methods to test the validity of the data obtained.

Descriptive analysis is used on collected data to provide a clearer and more in-depth picture of the phenomenon being studied, without generalizing the results. Qualitative data analysis in descriptive research consists of three main stages, according to Miles and Huberman (1994):

This study is expected to produce a comprehensive understanding of Emina product endorsements among teenagers through the Instagram account @tasyafarasya.

Therefore, @tasyafarasya is a celebrity with many followers who uses social media to build her image in the beauty industry. Her followers are interested in the content she creates, which makes them interested in the Emina products she promotes. As a celebrity endorser, @tasyafarasya creates engaging promotional content to introduce products and boost their popularity. @tasyafarasya uses Instagram as a promotional channel to market Emina products because it is highly popular. This is sure to increase product sales.

Most people who view the Instagram account @tasyafarasya say that @tasyafarasya is very skilled in beauty. This can be seen from the various makeup tutorial content she creates. Informant 1 stated that @tasyafarasya can combine makeup techniques with product selection that suits skin types, and informant 2 stated that @tasyafarasya appears to be very skilled in using makeup. Additional information, such as from informant 3, states that @tasyafarasya has a deep

understanding of beauty products and often provides helpful reviews for her followers. In terms of skincare, informant 5 says that @tasyafarasya has expertise that goes beyond just applying makeup; she also helps her followers choose the right skincare products.

Studies show that @tasyafarasya has successfully built strong credibility as an artist endorser in promoting Emina products on Instagram. According to the source credibility theory by Hovland and Weiss (1951), three main factors influence the credibility of a source: competence, trustworthiness, and attractiveness. In this case, @tasyafarasya demonstrates all three components very well, enabling her to deliver promotional messages that influence her followers.

After seeing the endorsement from @tasyafarasya, most informants said they were more interested in trying Emina products. This is in line with Hovland and Weiss's findings that source credibility has a significant influence on message acceptance and audience attitudes. @tasyafarasya has competence, a trustworthy reputation, and appeal that make her followers more confident in trying the promoted products. Her followers' confidence in the product's effectiveness is reinforced by clear and practical explanations about the product along with the personal experiences she shares.

Based on the results of the study, it can be concluded that @tasyafarasya has high credibility as a celebrity endorser in promoting Emina products through Instagram. This credibility is reflected in three main aspects according to Hovland and Weiss's theory, namely competence, trustworthiness, and appeal.

First, in terms of competence, the majority of informants assessed that @tasyafarasya has expertise and knowledge in the field of beauty, both in terms of makeup and skin care. Tasya's ability to convey information clearly, practically, and in accordance with the needs of the audience makes her a trusted source of information.

Second, in terms of trustworthiness, Tasya Farasya's honesty and openness in conveying the strengths and weaknesses of Emina products makes her reviews feel authentic and not merely commercial. This strengthens her followers' trust in the products she recommends.

Third, in terms of appeal, Tasya Farasya is able to build emotional closeness with her audience through her personal, energetic, and inspiring communication style. This appeal makes her content more interesting and influences the audience's interest in the products being promoted.

Although there has been an increase in the number of Tasya Farasya's Instagram followers from year to year, her content performance has fluctuated. This shows that the credibility of an endorser does not only depend on the number of followers, but also on the quality of delivery and emotional engagement with the audience.

Overall, the credibility of @tasyafarasya has proven to be able to influence the audience's interest in trying Emina products, making her an effective endorser in marketing products on social media.

This study has shown that the credibility of a celebrity endorser such as @tasyafarasya—including aspects of competence, honesty, and attractiveness— significantly influences teenagers’ interest in trying Emina products through Instagram. However, to broaden the understanding of this phenomenon, future research is encouraged to explore several additional aspects.

First, a comparative study can be conducted to examine the effectiveness of endorsements by various beauty influencers with different communication styles and follower counts, to identify the characteristics of the most impactful endorsers for the teenage market.

Second, a quantitative approach may be employed to obtain broader and more generalizable data by distributing questionnaires to a larger number of respondents.

Third, audience segmentation based on age and gender can be investigated further to determine whether endorsement effects differ among early and late teenagers, or between male and female adolescents. In addition, other social media platforms such as TikTok and YouTube could be analyzed to compare the effectiveness of different media in delivering product endorsements. Longitudinal research is also important to assess whether the influence of endorsements contributes to long-term brand loyalty. Moreover, a psychological approach can be used to explore how endorsements affect teenagers’ emotional responses and self-identity, particularly in relation to beauty perception and self- confidence.

Lastly, analyzing which content formats—such as reels, stories, or live sessions—are most effective may help brands design more targeted and impactful digital marketing strategies.

The authors would like to express their deepest gratitude to all parties who contributed to the completion of this research. We thank the Faculty of Social and Political Sciences, Communication Studies Program, Swadaya Gunung Jati University, for providing the academic support and resources necessary for this study.

Special thanks are extended to the informants who participated in the interviews, sharing their valuable insights and experiences that enriched the quality of this research. We also appreciate the guidance and encouragement from our lecturers and supervisors, particularly those who provided critical feedback during the research process.

Finally, we are grateful to our families and peers for their continuous support and motivation throughout the course of this study. This research would not have been possible without the collective support and contributions from all those mentioned.