InteractiVenn is a web-based tool designed for the analysis of sets through Venn diagrams, particularly useful in biological sciences. It offers a flexible interface for constructing and analyzing Venn diagrams with up to six sets, enabling users to explore set unions while preserving the diagram's shape. The tool supports interactive visualization of set unions guided by a tree or a list, allowing users to navigate through different levels of set combinations. Key features include the ability to adjust font size, opacity, and export diagrams in various formats. InteractiVenn has been applied to analyze biological datasets, such as comparing feature selection methods for candidate biomarkers in prostate cancer proteomics and distributing gene families among six plant genomes. The tool is freely available at www.interactivenn.net and is expected to be useful for a wide range of researchers and biologists.InteractiVenn is a web-based tool designed for the analysis of sets through Venn diagrams, particularly useful in biological sciences. It offers a flexible interface for constructing and analyzing Venn diagrams with up to six sets, enabling users to explore set unions while preserving the diagram's shape. The tool supports interactive visualization of set unions guided by a tree or a list, allowing users to navigate through different levels of set combinations. Key features include the ability to adjust font size, opacity, and export diagrams in various formats. InteractiVenn has been applied to analyze biological datasets, such as comparing feature selection methods for candidate biomarkers in prostate cancer proteomics and distributing gene families among six plant genomes. The tool is freely available at www.interactivenn.net and is expected to be useful for a wide range of researchers and biologists.