<p>Identifying the synergistic gain and distributional inequity of digital transformation in environmental governance is crucial for sustainable development. Using panel data of Chinese cities from 2011 to 2022, this study constructed a comprehensive indicator, which encompassed government digital attention, investment, and response, to characterize government digital transformation. Combining theories of information asymmetry and signaling, this study empirically investigated government digital transformation’s impact on pollution and carbon reduction. The results showed that government digital transformation achieved a synergistic gain in pollution and carbon reduction by promoting green technological innovation and green financial development. Disclosure of corporate environmental information and public environmental concerns negatively moderate the relationship between pollution and carbon reduction during&#xa0;digital government transformation. Moreover, disparities in internet penetration, population aging, resource dependence, levels of economic development, regional location, and urban agglomeration significantly shape the unequal distribution of pollution and carbon reduction outcomes associated with digital government&#xa0;transformation. This study offers new insights into both the benefits and inequalities of environmental governance in the digital era, and it carries important implications for advancing the Digital China strategy, achieving the dual carbon goals, and designing more&#xa0;inclusive digital governance policies.</p> Graphical abstract <p></p>