Abstract: The usefulness of social media in the digital era has turned retail investors to social media for financial information. This study aims to examine the effect of social media exposure, finfluencer (financial influencer) credibility, platform used for investment advice and herd mentality on retail investor's investment behavior in Chennai. The research identifies significant relationships of these digital factors with investment decisions using a structured questionnaire and quantitative analysis. According to the findings, exposure to social media enhances investor behavior in a positive way if content is considered credible and coincides with the collective market opinion.

Moreover, the research also uncovers that retail investors now tend to subscribe to finfluencers for last minute, readily understandable thought processes, resulting in a herd behavior against popularly held, rather than conventional analysis. This dynamic is evolving hence the investor should have financial literacy and critical thinking in the digital world. An outgrowth of work in progress, the results help investors, financial content creators and policy makers seek informed and responsible investment practice in the era of social media. This research also provides a way forward for future behavioral bias research on digital platforms for financial decision making.

Keywords: Finfluencers, Investment Behavior, Social Media Influence, Behavioral Finance, Digital Trust, Herd Mentality.

| DOI: 10.17148/IARJSET.2025.12722