GanttProject

It provides a desktop, G‑chart based project management environment that runs offline on Windows, macOS and Linux. Users can break down work into tasks, assign resources, calculate costs, and generate reports, with the ability to import and export Microsoft Project files as well as CSV, Excel, PDF and PNG formats.

The interface is designed to be simple and uncluttered, allowing project managers in fields such as construction, architecture, engineering, media production and other small‑to‑medium enterprises to start new projects quickly without extensive configuration. Collaboration can be extended through an optional cloud‑based server that synchronises project data.

The software has been maintained since 2003, is released under the GPL‑3 license, and is available free of charge with an optional donation‑based model. It supports multiple languages and is used by thousands of users worldwide.