Supplemental data for "Comparison of measured and simulated spin-wave mode spectra of magnetic nanostructures" by H. T. Nembach, R.D. McMichael, M.L. Schneider, J.M. Shaw, T.J. Silva.1) Experimental spectra of approximately elliptical, 100 nm or 200 nm elliptical magnetic structures. 2) SEM images of the magnetic structures 3) Scripts and data used in micromagnetic modeling and simulated measurements of the structures. Experiment: In this work, we prepared two sets of Ni80Fe20 elliptical nanomagnets with nominal long axes lengths (short axes lengths) of 240 nm (200 nm) and 120 nm (100 nm): Thin-film layers of 3 nm Ta/10 nm Ni80Fe20/5 nm Si3N4 were dc-magnetron sputtered onto a sapphire substrate before a 15-nm diamond-like carbon (DLC) layer was deposited via ion-beam deposition in a separate vacuum chamber. The spin wave mode spectra of the magnetization dynamics were measured with a heterodyne magneto-optical microwave microscope (H-MOMM) Simulations: We carried out micromagnetic simulations using the Object Oriented MicroMagnetic Framework (OommF). To determine the shape for modeled nanomagnets, greyscale SEM images of the nanomagnets were converted into binary images using a thresholding algorithm. The original SEM images were given a Gaussian blur over 1.4 nm (3 pixels), rescaled by 25 % and given a secondary blur over 3.8 nm. A threshold value was determined using Otsu's method. The simulated spectra were extracted from impulse response calculations made at an array of applied field values in the experimental range. The modeling also provides the spatial profile of the spin wave modes. The bulk of the data is associated with the micromagnetic modeling. Files include OommF input '.mif' scripts, sample masks, modeling output and python scripts for analysis and plotting, and the resulting figures.