Freestanding networked nanoparticle (NP) films hold substantial potential due to their high surface areas and customizable porosities. However, NPs with high surface energies and heterogeneous sizes or shapes present considerable challenges as they tend to aggregate, compromising their structural integrities. In this study, we report the scalable fabrication of ultrathin, bicontinuous, and densely packed carbon NP films via Pickering emulsion-mediated interfacial assembly. This method enables the efficient transfer of closely packed NP networks from emulsions to air-water interface and ultimately to diverse substrates, which provides broad versatility for tailored applications. Utilizing the jamming structures of NPs at the fluid interface, we achieve precise control over film size with homogeneous thickness while minimizing material waste and facilitating recyclability. Notably, the films can be smoothly transferred to micropatterned, stretchable, and complex three-dimensional substrates, enabling the realization of robust conformal coatings. The resulting films exhibit high structural stability and flexibility, demonstrating significant potential for the design of stretchable and flexible devices.