This paper compares the evolution of inequality of opportunity (IOP) in labor market earnings in Brazil and India from the late 1990s to early 2010s using a regression tree machine learning approach. Parental education is the main driver of IOP in both countries. High-caste individuals in India and whites in Brazil earn more, and gender disparities have grown, with low-caste and black women facing the greatest disadvantage. In Brazil, IOP has remained stable despite falling earnings inequality. In India, it has declined slightly but remains higher, accounting for over 30% of wage inequality. These findings highlight the complex interplay of structural factors underlying IOP and reinforce the need for well-targeted, evidence-based public policies to promote greater equity in the labor market.