OriginLab Origin Project (.opju)
.opjuOriginLab Origin / OriginPro (2018 and later — the ZIP-based project format that replaced .opj)
What it is
The project file OriginLab's Origin/OriginPro software saves when you hit "Save" — a single file bundling every worksheet (book/sheet/column), every graph, and every fit result from a session. Internally it is a ZIP container of proprietary binary-encoded segments (LIST blocks), not a documented format.
Who produces it
Researchers and labs using OriginLab Origin or OriginPro for plotting and curve fitting — one of the most common commercial plotting tools in physics, chemistry, and materials-science labs. Anyone without a paid Origin license who receives a colleague's .opju file cannot open it at all without this kind of reader.
What we read / what we don't read
What we read
- Numeric columns (double-precision and integer)
- Text columns
- Date/time columns
- Empty cells (preserved as empty, not dropped or zero-filled)
- Mixed-type columns
- Book/sheet/column topology (workbook and worksheet structure)
- Sheet names
- Column Long Names
What we don't read
- Graphs (plot definitions, axes, styling)
- Fit results (parameters, residuals, statistics)
- Matrix sheets (Origin's separate matrix-book object type)
- Cell/column formatting (number formats, colors, fonts)
- Notes windows
- LabTalk scripts embedded in the project
How to import it into AltaiPlot
- Open AltaiPlot and choose File → Import (or drag the .opju file onto the window).
- AltaiPlot detects the .opju signature automatically — no need to pick a format manually.
- Every book/sheet in the project is listed; pick the one(s) you need.
- Preview the columns (names, types, first rows) before committing.
- Click Import — numeric, text, date/time, and empty cells land in a normal AltaiPlot sheet, ready to plot or re-fit.
Auditability note: this page's capability claims are sourced fromsrc/renderer/src/engine/v7/import/importers/OriginProjectImporter.ts:16 — see the full format list for every extension AltaiPlot recognizes.