Organic thin-film transistors (OTFTs) are drawing increasing attention due to their unique advantages of mechanical flexibility, low-cost fabrication, and biodegradability, enabling diverse applications that were not achievable using traditional inorganic transistors. With a growing number of complex applications being proposed, the need for expediting the design process and ensuring the yield of large-scale designs with organic technology increases. A complete digital standard cell library plays a crucial role in integrating the emerging organic technology into existing computer-aided-design (CAD) flows.In this paper, we present the design, fabrication, and characterization of a standard cell library based on bottom gate, top contact pentacene OTFTs. We also propose a commercial tool compatible, RTL-to-GDS flow along with a new organic process design kit (PDK) developed based on our process. To the best of our knowledge, this is the first open-source organic standard cell library, enabling the community to explore this emerging technology.