Amphipathic helices (AHs) detect differences in bulk membrane properties, but how AHs detect the nuclear membrane surrounding the genome is not well understood. Here, we computationally screened for candidate AHs in a curated list of characterized and putative human inner nuclear membrane (INM) proteins. Cell biological and in vitro experimental assays combined with computational calculations demonstrate that AHs detect lipid packing defects over electrostatics to bind to the INM, indicating that the INM is loosely packed under basal conditions. Membrane tension resulting from hypotonic shock further promoted AH binding to the INM, whereas cell-substrate stretch did not recruit membrane tension-sensitive AHs. Thus, distinct mechanical inputs enhance lipid loosening at the INM to different degrees, which AHs in INM proteins may harness for downstream biochemical functions. Our resource provides a framework for future studies on the contributions of lipid-protein interactions at the INM and enables exploration of the membrane properties of the INM under different conditions.