Accurate prediction of match outcomes and objective assessment of athletic performance are crucial for both athlete development and strategic planning in competitive sports. The International Judo Federation (IJF) ranking system is widely adopted in judo; nevertheless, it has limitations in accurately assessing athletic performance owing to its strong dependence on tournament participation frequency. This study aimed to develop an athletic performance assessment and victory prediction system using the Elo rating system for practical judo competitions. Approximately 380,000 match results derived from IJF-organized tournaments from 2009 to 2024 were analyzed in this study. Each athlete’s Elo rating was calculated, and match win rates were derived from rating differences. Additionally, the championship win probability and top-four finish probability for the 2024 Abu Dhabi World Championships and Paris Olympics were estimated by incorporating the match win rates and tournament draw data. The estimated match win rates closely aligned with the actual match results, particularly with small rating differences; however, significant overestimations were observed in matches with larger rating differences. The combination of Elo rating-based win rate estimation and tournament draw data across multiple weight classes was more strongly correlated with actual tournament results than IJF rankings. These findings suggest that the Elo rating system not only serves as an effective tool for assessing athletic performance and predicting match outcomes in judo athletes but is also a dynamic alternative to traditional ranking systems, laying the groundwork for improved strategic tools with potential applications in other individual sports.
