A facile, rapid, and noninvasive method for monitoring transesterification of acylglycerols for the application of biodiesel production is reported. High-field NMR spectroscopic analysis prevents incorrect and overintegration of signals that have previously been combined due to crowding on low-field NMR spectrometers. Using high resolution NMR, a new and more accurate equation utilizing a nonoverlapping signal is presented for calculating biodiesel conversion. Here, we demonstrate the kinetic acquisition of high-resolution NMR spectra for real-time monitoring of the consumption and formation of triacylglycerols, diacylglycerols, and fatty acid methyl esters in biodiesel production. This method of reaction monitoring takes place on small scale in a standard NMR tube, is acquired with existing laboratory instruments, and avoids taking aliquots from a reaction. By comparing different catalysts and conditions, this method facilitates the selection/optimization of catalysts and may improve quality in compliance with fuel standards by assessing the reaction composition for models of an :industrial transesterification system. Using this method, H2SO4, NaOH, and 1,5,7-triazabicyclo[4.4.0]clec-5-ene (a bifunctional, nonionic base) have been compared as catalysts for transesterification.