In this study, we pay special attention to the effects of social capital in crowdfunding performance. Previous researches already investigate the influencing factors of crowdfunding performance, but the influence mechanism of social capital on crowdfunding performance is unclear. We first explore the effects of social capital on crowdfunding performance through an empirical study based on the large-scale real-world dataset with 103,582 campaigns collected from Indiegogo. The empirical results suggest social capital has remarkable influence on crowdfunding performance. Some interesting findings are indicated. For example, the longer descriptions about campaigns improve the crowdfunding performance, but the longer descriptions about campaign owners worsen the crowdfunding performance. In addition, we deeply test the moderating effects of campaign category. Then we further develop a prediction method for crowdfunding performance from the perspective of social capital. The experiments demonstrate the effectiveness of our social capital-based prediction model. •Campaign owners' social capital has remarkable effects on crowdfunding performance.•A prediction model for fundraising performance based on social capital is proposed.•Campaign category moderates effects of social capital on crowdfunding performance.•A comprehensive representation of campaign owners' social capital is proposed.