Crowdfunding endows entrepreneurs with a means of kickstarting their businesses. The amount of investment that can be elicited through crowdfunding campaigns often surpasses fundraisers’ expectation, leading to market inefficiencies. Y et, this phenomenon of overfunding has garnered relatively little attention in past studies. Subscribing to signaling theory, we strive to shed light on the causes of overfunding by positing crowdfunding platforms as fertile breeding grounds for herding behavior. Specifically, we attempt to capture the dynamic nature of herding by decomposing herds on crowdfunding platforms into their constituent dimensions of maturity, intensity, and persistency. We further endeavor to explore how these constituent dimensions shape overfunding. This study advances a model to testify to the instrumental role of initial herds in amplifying overfunding on the crowdfunding platforms, which in turn could offer insights into remedying the problem of overfunding.