Systems and methods for fast and robust quantification of magnetization transfer (MT) using off-resonance spin-lock MRI. The techniques can be insensitive to variations of the inherent relaxation rates R1 (1/T1) and R2 (1/T2) of the free-water pool and to variations of the chemical exchange pool. The techniques can also be robust in the presence of inhomogeneity in the B1 RF and/or B0 magnetic fields.