Abstract Magma decompression rate is one of the most important parameters in controlling eruption dynamics. One way to determine decompression rate is by fitting a volatile elements diffusion profile to a concentration gradient in crystal‐hosted embayments. Previous studies have used a variety of diffusion models, limiting the possibility for inter‐study comparison. Here, we introduce EMBayment‐Estimated Rates (EMBER), a standalone versatile tool that models diffusion of volatile elements along melt embayments. Our model relies on the pdepe function of MATLAB to calculate diffusion profiles of H 2 O, CO 2 , and S through the finite difference method. EMBER uses a grid search seeking out the best fits for decompression rates, initial dissolved concentration of each studied volatile and initial exsolved gas content, while setting three constants: temperature along the ascent and pressure at the beginning and end of the ascent. Our model can compute the rate for basaltic, intermediate, and rhyolitic compositions. We applied EMBER to previous studies to evaluate and validate our model. We then reprocessed “homogeneously” the raw data from the literature for a comparison. In other words, the same protocol was used for each diffusion profiles removing the literature‐specific strategies used to constrain unknown parameters. With this comparison, we found a statistically significant positive correlation between maximum magma decompression rates and explosivity of the related eruption. EMBER is expected to help increase the number of volatile diffusion in embayments studies aiming at constraining magma decompression and ascent rates and to facilitate inter‐study comparisons. Key Points EMBayment‐Estimated Rates (EMBER) is a new, freely available, Graphical User Interface software that models magma ascent rates for basalt to rhyolite with H 2 O, CO 2 , and S diffusion profiles EMBER was validated by reproducing previous published literature data For mafic eruptions, we found a notable correlation between maximum recalculated decompression rates and eruption magnitude or plume height