The BLING (Biogeochemistry with Light, Iron, Nutrients and Gas) model is an intermediate-complexity computational tool designed to simulate the global biogeochemical cycling of essential elements and their isotopes within ocean general circulation models (GCMs). It provides a computationally efficient yet realistic representation of marine biogeochemistry, making it a valuable resource for researchers studying ocean processes and climate change. The model aims to strike a balance between scientific comprehensiveness and computational feasibility, allowing for its integration into complex Earth System Models. Originally developed in FORTRAN (F90) by Eric Galbraith and collaborators at Princeton / GFDL, BLING has undergone several iterations. The initial version (v0) focused on a single macronutrient, typically phosphorus (representing both P and N), and the micronutrient iron. A significant update, BLINGv2, was later released, expanding its capabilities to include nitrogen cycling and a more intricate representation of the marine ecosystem, such as three distinct phytoplankton classes. This version manages six prognostic tracers: dissolved inorganic carbon (DIC), alkalinity, phosphate, dissolved iron, dissolved organic phosphorus (DOP), and oxygen (O2). BLING is designed to be fully prognostic, with its behavior determined by the physical environment of the ocean GCM, and it implicitly handles living pools and particulate organic matter diagnostically to minimize computational overhead. It is compatible with GFDL's Modular Ocean Model (MOM) versions, including MOM4p1, GOLD, MOM5, and MOM6, and can also be adapted for use with other ocean models like MITgcm, UVic, ROMS, and NEMO. This model is widely applied in oceanography, marine science, and climate science research. It is particularly useful for investigating the physical-biogeochemical interactions that govern the distribution of nutrients and oxygen in the ocean, as well as for studying ocean carbon storage, hypoxia, and biological productivity under various climate change scenarios. Its low computational cost allows for its use in higher-resolution simulations and its integration into large-scale Earth System Models, including those participating in intercomparison projects like CMIP6. Additional functionalities include optional carbon cycle modules, radiocarbon tracing, nutrient source tagging, and parameterizations for sediment processes and diel vertical migration. While BLING offers a robust framework for many biogeochemical studies, its simplified ecosystem representation means it does not explicitly resolve the diversity and internal dynamics of marine ecosystems, which may lead to certain biases in highly productive or oligotrophic regions. BLING is continuously developed and refined, with O2 equilibria and gas exchange following OCMIP2 protocols. Its design allows for the inclusion of additional isotopic tracers with minimal code modifications, providing flexibility for specialized research. Researchers can leverage this model for a broad range of applications, from understanding fundamental ocean biogeochemical processes to projecting future changes in marine environments. The model's open-source nature encourages community contributions and adaptations for specific scientific purposes, ensuring its continued relevance and utility in the field of ocean modeling.