We assess the numeracy (age heaping) of religious minorities, particularly Jews, and other defendants of the Spanish and Portuguese Inquisitions, and compare it with the general Iberian population. Our database includes 13,000 individuals who took part in Inquisition trials, and 17,000 individuals recorded in censuses and parish registers who serve as a control group. We thoroughly discuss the representativeness of our samples for the populations we aim to capture. Our results point at a substantial numeracy advantage of the Judaism-accused over the Catholic majority. Furthermore, Catholic priests and other groups of the religious elite who were occasional targets of the Inquisition had a similarly high level of numeracy.