In today’s educational landscape, digitalization, driven by economic interests, has become increasingly prominent. This development has sparked interest in understanding how high school students’ technical capital and mathematical self-efficacy influence their outcomes. To deepen the understanding of this interplay, this study integrates Selwyn’s Bourdieusian capital theory on technical capital with Bandura’s theories on mathematical self-efficacy. Empirical data were collected through a survey administered to 208 high school students across three schools in Sweden, ensuring anonymity and integrity. Linear regression was employed, controlling for gender, academic program, socioeconomic factors, and completed coursework. The results demonstrate that technical capital significantly predicts mathematical self-efficacy, with a predictive capacity of up to 59.6%. Moreover, tolerance for deviation in the model increased the predictive capacity to 94.2%. No significant differences in predictability were observed based on gender or academic program dependencies. However, gender differences revealed a more linear relationship between technical capital and digital/technical competence among women compared to men. Additionally, both genders displayed equivalent performance in knowledge-based questions. This suggests that men tend to overestimate their digital competence relative to their technical self-efficacy, while women do not exhibit the same tendency toward overconfidence. In conclusion, this study offers insights into how technical capital and self-efficacy in mathematics shape students’ educational outcomes.