1Tree

See disk usage as an expandable folder tree

1Tree is a Windows utility from TriSun Software for viewing the size of drives, folders and files in one navigable tree. It helps users locate where storage is being used without opening each folder in a separate Explorer window. Selecting a drive or folder loads its immediate contents and their sizes; users can drill further down, sort items by size and use the displayed totals to decide what needs attention.

Free 1Tree and the Pro edition

The developer offers two editions. The free 1Tree displays sizes throughout the folder tree and provides common actions for individual items. 1Tree Pro adds batch operations, allowing several checked files or folders to be handled together. Both editions can sort by size, use readable units and decimals, copy a full path, run or open an item, display its properties and adjust parts of the interface.

• Find large items: expand a drive or folder and sort its contents by size to identify what is using space.
• Work with paths: copy a full path or open an item directly from the utility.
• Manage selected files: Pro adds batch actions such as moving, copying, renaming and sending selected items to the Recycle Bin.
• Check network locations: the preferences include mapped network drives, subject to enabling the relevant option.

Use file-management commands carefully

1Tree is a space-analysis and file-management aid, not an automatic cleanup system. Its Pro edition includes commands to move items to the Recycle Bin or permanently delete them. Confirm the selected paths and contents before applying a batch action, and keep a separate backup of important files. A large folder is not necessarily disposable: applications, Windows components and working project directories may rely on files that appear unfamiliar.

The current download page lists 1Tree Free v7.0 and 1Tree Pro v8.0. The program is advertised for 32-bit and 64-bit Windows, from older systems through Windows 11, and its interface is available in multiple languages including English and Spanish. The release history shows those versions last updated in 2021, so check compatibility and current licensing information before installing on a newer system.

1Tree is a downloadable desktop utility rather than a local repair or consulting service. The basic edition can be a straightforward way to inspect disk usage; Pro is aimed at users who regularly need to compare and manage groups of files.