FlexHex is a freeware hex editor for Microsoft Windows that can edit files, NTFS alternate streams and sparse data, OLE compound files, logical disks, and physical drives.

The original file is kept intact and gets modified only when the user selects the Save command.

FlexHex is written on Visual C++ and MFC, which makes it very fast while keeping the size small enough.

In addition to the standard features more or less typical for other hex editors, FlexHex offers a few unique ones.

Specifically, FlexHex is the only hex editor that can create or edit NTFS alternate streams, sparse files, and OLE structured storage.