CEST fingerprinting was recently proposed to achieve efficient exchange rate quantification for pH mapping. Here we present the initial data of pH mapping in healthy subjects and one acute stroke patient at clinical scanners in an 8-min scan using CEST fingerprinting. The pH maps of the healthy volunteers are homogenous and the values fall in the normal physiological range. The pH map in the patient shows an inhomogenous acidic area. This study shows CEST fingerprinting has the potential to detect acidosis in human subjects.