Metal-organic frameworks (MOFs) are a class of crystalline materials built from inorganic nodes and rigid multitopic organic linkers using reticular chemistry. The combination of the structural rigidity and directional coordination of the inorganic nodes, which can be either metal ions (e.g. in ZIF-8) or polynuclear clusters (e.g. in UiO-66 or MOF-5), with the rigid linkers determining the possible architectures of the resulting MOF. This is summarized in the secondary building unit (SBU) concept. Using these synthesis concepts, a vast space of MOF chemistry can be accessed, leading to the discovery of materials with very high porosity and an unusual chemical and thermal stability. The application of MOFs is being explored in a variety of fields, including catalysis, gas storage, gas separation, sensing and electronic devices, harnessing these exceptional properties and the tunability offered by the chemistry of MOFs. The modular nature of the MOFs allows for mixed linker MOFs, termed multivariate (MTV-)MOFs, and post-synthetic modification of the linkers and capping agents. Substitutions and mixed metals in the inorganic nodes are also possible. Another approach that is often explored to tune MOF properties is defect engineering, attempting to control the defect density of either missing metal ions/clusters or missing linkers. Defects can be introduced using modulators, i.e. monotopic ligands, or by tuning the synthesis parameters. The porous nature of the explored MOFs furthermore allows for the trapping of guests, which can be molecules that are added by design, but can also include residual solvent/template/modulator/linker from the synthesis. The final stoichiometry of a MOF then should account for the metal nodes, linkers, capping agents and guests. In this work, we aim to show that a combination of digestive, liquid-state H quantitative nuclear magnetic resonance spectroscopy (qNMR) and thermogravimetric analysis (TGA) under air is sufficient to determine the stoichiometry of MOFs in most cases, while for the more complicated cases combinations with additional characterization techniques are recommended. Extra attention is given to the practical considerations of qNMR.