Recent advances in single-molecule force spectroscopy enabled scientists to include mechanical force as another thermodynamic variable that can be precisely controlled. We developed high-speed, high-resolution magnetic tweezers that interrogate nucleic acids, proteins, and their complexes. Applications of these methods often revealed the unexpected force-dependent nature of a molecular interaction. Expanding the toolkit for mechanobiology, we will investigate the response of cells toward mechanical stimuli through a multiscale approach at the levels of signaling molecules, cytoskeleton, and cellular network.