Cybercrime presents increasing challenges to digital societies, yet population-level research on offenders remains limited, particularly in Sweden. This longitudinal study used national register data (2000-2022) to examine demographics of Swedish cybercrime offenders. Cybercrimes included online fraud, crimes against children, online threats, and other digital offenses. The proportion of offenders increased steadily over time, with men twice as likely as women to be involved. Most offenders were aged 20-39 and had low income and low educational attainment. Prior offline crime was common, suggesting overlapping criminal trajectories. Divorced and never-married individuals had higher odds of committing cybercrime. Socioeconomic profiles varied by offense type; child exploitation offenders were typically older with fewer offline crimes. Findings highlight the need for targeted interventions and further data to understand and prevent cyber-offending effectively.