Over the past two decades, quantitative models and statistical methods have been increasingly applied to syntax research, with treebanks emerging as a vital resource for this field. However, tools specifically designed for calculating syntactic metrics remain relatively scarce compared to traditional word frequency measures. This gap hinders the deeper integration of quantitative methods into syntax research. In response, we have developed a tool called QuanSyn, which is tailored for quantitative syntax analysis. Based on treebanks, QuanSyn can calculate metrics such as dependency distance, hierarchical distance, dependency direction, and valency-related syntactic metrics. Additionally, it facilitates the construction of linguistic networks and rapid fitting of functions. QuanSyn can help lower the barriers to accessing syntactic quantitative analysis, thereby promoting the broader application of quantitative methods in syntax research.