Numeric data to HDF5
Create a single selected HDF5 dataset from a numeric matrix or an exported JSON envelope.
Drop your files here
Make something new. Keep everything private.
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
- JavaScript Object Notation (.json)
- Comma-separated values (.csv)
Output format
Hierarchical Data Format 5 (.h5)
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 Numeric data to HDF5
- 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
- 2 million finite numeric elements. CSV requires a rectangular matrix without a header and writes float64.
- JSON must contain flat data, shape and dtype. Creates a new file with one dataset; does not preserve source attributes.
Engine: h5wasm. The engine may need a first-use download. Your file stays in this browser session.Check conversion engines and offline requirements.
Conversion settings
These settings are available in the converter above.
- Dataset path
- Inspect the HDF5 file and enter an explicit path, such as /measurements. JSON keeps all dimensions; CSV accepts 1D / 2D only.
About this conversion
Is numeric data to hdf5 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.
- HDF5 dataset to JSON
Select one numeric HDF5 dataset and export its values locally.
- HDF5 dataset to CSV
Select one numeric HDF5 dataset and export its values locally.
- Inspect HDF5 scientific file
List datasets, dimensions and datatypes in HDF5, Loom, MuData and HDF5-based NetCDF4 files.
- Create TAR.GZ
Bundle selected files into a gzip-compressed USTAR archive.
- Create ZIP
Bundle the selected files into one compressed ZIP archive.
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