The sharp rise in global temperature is a major threat to human survival. This issue poses a common challenge for the entire world, and we must halt the trend of an anomalous increase in the Earth's temperature and achieve carbon neutrality. It is important to note that there is a lack of cross-database scientometric perspectives on carbon neutrality, thus creating wide opportunities to mine new knowledge. In this study, using the advanced R-tool bibliometric software, we conducted a systematic review of 41,459 carbon-neutral research outputs listed in the Web of Science and Scopus databases between 1939 and 2023. This review provides new fundamental knowledge and reveals possible directions for future endeavors to gain a more comprehensive understanding of carbon neutrality. Our study observed that reaching the goal of carbon neutrality research requires concerted efforts from countries around the world, with China, the United States, and the United Kingdom leading the research. In the future, carbon-neutral research will focus on carbon emissions control, clean energy utilization, and the resulting environmental, social, and economic impacts. Therefore, international cooperation and collaboration and the formulation of rational and long-term development plans are critical to achieving carbon neutrality.