.opj file: how to open it on Windows

2 Windows apps register the .opj extension. Install one of them to open the file with a double-click.

About the format

Format

Origin Project Format

PRONOM identifier

fmt/1123, fmt/1572

Format data: freedesktop.org shared-mime-info and PRONOM (The National Archives, UK).

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  LabPlot2

  FREE, open source and cross-platform Data Visualization and Analysis software accessible to everyone and trusted by professionals

  Open source 2.12.1 4.4K ↓
• L
  LabPlot2 (AppX)

  A free, open source spreadsheet, data visualisation, and analysis software accessible to everyone.

  Open source 2.1201.10343.0

Related guide: Change the default app for a file type in Windows