Matrix Market to JSON
Export Matrix Market sparse data as JSON with explicit shape and precision limits.
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Multiple files welcome · processed one at a time
Select a tool to see its supported formats and conversion limits. Large files may exceed your browser’s memory.
Before processing large files
On phones and tablets, start with files under 20 MiB and keep this tab in the foreground. Video, OCR and 3D operations can use several times the input size in memory. Desktop browsers generally have more room, but the 128 MiB job limit is not a guarantee that every file will fit. Smaller batches reduce memory pressure.
Supported input formats
- Matrix Market sparse coordinate matrix (.mtx)
Output format
JavaScript Object Notation (.json)
Support applies to this conversion direction. Check the limits below for features that may change or be discarded.
Compare all supported formats and conversion limits →How to use Matrix Market to JSON
- Add your supported file using the chooser or drop zone.
- Review the settings and conversion limits before processing.
- Select Convert files, then download the result.
What to expect
- Maximum 64 MiB and 2 million stored values/coordinates; each dimension is at most 2 million. Only finite values are supported. Dense CSV is capped at 2 million cells.
- Matrix Market coordinate real, integer or pattern; general or symmetric only. JSON retains 1-based coordinates and symmetric storage. Duplicate coordinates are summed, with unsafe integer sums rejected. CSV expands symmetric entries. Complex, array, skew-symmetric and Hermitian formats are unsupported.
Engine: Local scientific matrix parser. The engine may need a first-use download. Your file stays in this browser session.Check conversion engines and offline requirements.
About this conversion
Is matrix market to json free?
Yes. This tool runs on your device without an account or a conversion fee.
Are files uploaded during conversion?
File processing happens locally in your browser. Engines may download their code on first use; your input files are not sent to a conversion server. Read how file privacy works.
What if conversion fails?
Check that the file matches a supported input, review the engine’s limitations and try a smaller representative file. If the engine cannot load, check its engine assets and browser requirements. The app reports failures without switching to a remote converter.
Continue with your output
These tools accept this tool’s output format. Each step has its own settings and fidelity limits.
- Numeric data to HDF5
Create a single selected HDF5 dataset from a numeric matrix or an exported JSON envelope.
- JSON to CSV
Convert JSON locally with an explicit structured-data mapping.
- JSON to TSV
Convert JSON locally with an explicit structured-data mapping.
- JSON to YAML
Convert JSON locally with an explicit structured-data mapping.
- JSON to XML
Convert JSON locally with an explicit structured-data mapping.
- JSON to SQLite database
Create a portable, single-table SQLite database from JSON records.
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