Gruff

The free-form nature of triple-stores offers a lot of flexibility for constructing databases, but that freedom can also make it less obvious how to find arbitrary data for retrieval, error-checking, or general browsing. Gruff is a freely downloadable graphical triple-store browser that attempts to make data retrieval more pleasant and powerful with a variety of tools for laying out cyclical graphs, displaying tables of properties, managing queries, and building queries as visual diagrams.

For more information please visit Gruff website: https://franz.com/agraph/gruff/.