The entirely reinvented social media marketing made through AI has allowed the online vendors to tailor their posts, advertisement and communication strategies in real time based on customer information and purchase behavior. The study focuses on the impact of AI-based personalization on the performance of online sellers on social media. We questioned 345 people, counted the extent of personalization of their marketing, performed a bit of statistics, a t-test between the high-AI and the low-AI users and put a regression equation to determine whether the AI personalization has anything to predict the performance. The statistics indicate that the vast majority of sellers in AI personalization are rated rather high as well as the effectiveness of their marketing. The t -test shows that the people who personalize their AI more realize statistically significant better marketing results than the ones who do not. Further, this observation is proved by regression analysis: AI personalization explains the performance by about 26.2 percent. All these findings support the value of AI tools in achieving the target audience, maintaining customer interest, and improving the overall results. These observations can help sellers use AI personalization as a competitive edge in the digital market that is quickly developing.