We propose a fully nonparametric framework to test to what extent technological change is factor-biased and heterogeneous. We show in a Monte Carlo simulation that our framework resolves the endogeneity issue between productivity and input choice and provides accurate estimates of firm-specific biases. For all Belgian manufacturing industries analyzed, we reject the predominant assumption of Hicks-neutral technological change over the period 1996–2015. We find that technological change is skill-biased, capital saving and domestic materials using. Moreover, we find significant heterogeneity in the pattern of technological change between and within industries. Relying on a rich dataset of firm characteristics, we provide robust indications that firm-level technological change can be attributed to specific firm strategies and technological characteristics.