Free Data Worth Sharing

NeuroJSON.io is an NIH-funded open data portal for neuroimaging datasets, designed to make scientific data:

• Findable: Fully searchable metadata and datasets
• Accessible: Open, lightweight JSON format
• Interoperable: Compatible across platforms and programming languages
• Reusable: Rich metadata, visualizations, and long-term viability

NeuroJSON leverages modern web technologies and scalable NoSQL databases and the JSON standard to distribute large-scale, complex imaging data in a human- and machine-readable form.

• Search — Browse across multiple databases, datasets, and modalities
• Preview — Interact with JSON metadata and visualize imaging data (2D/3D) in browser
• Download — Retrieve datasets in JSON format, ready for use in Python, MATLAB/Octave, C++, and more
• Upload - Contribute your own datasets to NeuroJSON.io (Steps to contribute)
• REST API — Automate your workflows with lightweight endpoints, designed for smooth integration into both local analyses and large-scale pipelines

1. Visit https://neurojson.io
2. Use the search page to find datasets or subjects of interest
3. Click any dataset to preview or download data
4. For automation, use the REST API

We welcome your datasets!

• NeuroJSON prefers BIDS-compliant data
• Convert datasets to JSON using NeuroJSON Client(neuroj):
  • Install Docker (skip this step if you already have it): Get Docker
  • Download neuroj via docker:

    docker pull openjdata/neuroj:v2025
    

  • Example (convert a single dataset to JSON via neuroj):

    docker run openjdata/neuroj:v2025 neuroj -i /path/to/database/rootfolder -o /path/to/output/json/folder -db openneuro -ds ds000001 --convert
    

  • See the full list of available NeuroJSON Client commands
  • Watch our tutorial video - convert data

1. Download NeuroJSON Client (neuroj)
2. Convert your dataset to JSON
3. Validate metadata
4. Open a ticket to upload your dataset

Contributions ensure long-term public availability and reusability.

• Lightweight endpoints for download
• JSON responses designed for integration with cloud and local workflows

Example (Load by URL with REST-API in Python):

pip install jdata bjdata numpy

import jdata as jd
data = jd.loadurl('https://neurojson.io:7777/openneuro/ds000001')

# List all externally linked files
links = jd.jsonpath(data, '$.._DataLink_')

# Download & cache anatomical nii.gz data for sub-01/sub-02
jd.jdlink(links, {'regex': 'anat/sub-0[12]_.*.nii'})

• NIH-funded data dissemination service
• Maintained by the COTI Lab, Northeastern University
• Contact: [email protected]

We’re continuing to grow NeuroJSON.io to better serve the community. Some of the upcoming directions include:

• 🔜 Expanding databases and datasets — broadening coverage to include more sources and subjects
• 🔜 Enhancing visualization — improving 2D/3D previews for richer and more intuitive exploration of data
• 🔜 Streamlining uploads — introducing new features to make dataset contributions more automatic and user-friendly