Impact of population aging and the digital economy on carbon regulation and its trend prediction

China, the world's largest aging society, faces the dual challenges of rapid population aging and “getting old before getting rich”, while the digital economy has emerged as an important factor shaping economic and governance transformation. Using provincial panel data for 2011–2022, this study applied an extended STIRPAT model to examine how population aging and the digital economy affect carbon regulation and predicted future trend under multiple scenarios for 2027–2050. The results show that population aging and the digital economy both weaken carbon regulation, whereas economic development level and industrial upgrading strengthen it. The digital economy mitigates the adverse effect of population aging on carbon regulation. Regional heterogeneity exists, with population aging significantly reducing carbon regulation only in central China, while the effects of the digital economy vary across regions, promoting carbon regulation in central China but inhibiting it in western China. Scenario simulations suggest that carbon regulation will continue increasing, with its growth rate exhibiting a trend of “fast first and then slow”, and scenario S2 showing the fastest growth trajectory. These findings suggest that future carbon regulation should adapt to different demographic and digital development pathways to maintain its mitigation effectiveness. This study provides evidence for optimizing carbon regulation pathways.