Bringing to light income and diploma inequalities. On the ‘stratificationist’ efficiency of the PCS Classification, the ESeG classification and the Employment class schema. Occupational classifications are among the main tools for objectivizing the structure of a society and they are sometimes used to grasp the inequalities within it. This paper aims at offering several indicators designed to assess occupational classifications’ ability to shed light on the unequal distribution of resources between social groups. Three classifications are here studied: the French PCS-2003 and the French Employment class schema from INSEE and the European ESeG classification. After recalling their principles and objectives, we lay down the usual procedures used to assess occupational classifications and we show that they don’t aim to grasp their ability to reflect social stratification. Using fractiles, which are commonly-used tool for analysing inequalities, we then offer two sets of indicators designed to assess the occupational classifications’ efficiency to reflect the slope, the shape and the extent of the inequalities in a population. Using these tools and data from the 2017 French Labour Force Survey, we show that at the aggregate level of the classifications studied, it is the four Employment class schema that best captures the unequal distribution of income and diplomas between population groups, whereas at the detailed level, it is rather the PCS. We finally put forward proposals for recomposing some of the categories of the PCS and the Employment class schema so as to make these classifications more efficient to reflect social stratification.