SPHERE (Synthetic Privacy via Hypersphere Rotation of Entries) is a macOS desktop app for generating and evaluating synthetic tabular data. It runs entirely on your Mac — no data leaves your machine.
- Synthetic data generation — generate privacy-preserving synthetic versions of your tabular CSV datasets
- Fidelity evaluation — compare mean, variance, correlation structure, and marginal distributions between real and synthetic data, scored 0–100
- Privacy risk assessment — measure singling-out, linkability, and inference attack risk, normalised against a baseline so scores are meaningful across datasets
- AI-powered analysis — ask questions about your data in natural language; Claude writes and runs analysis code on your behalf using your own API key
- Cloud sharing — share synthetic datasets and evaluation certificates via Dropbox or S3-compatible storage; your data never passes through SPHERE's servers
Download the latest release from the Releases page.
- macOS 12 (Monterey) or later
- Apple Silicon (M1 / M2 / M3 / M4)
- A SPHERE license key — contact zihuai@stanford.edu or visit sphere.stanford.edu
- An Anthropic API key for AI-powered analysis (optional)
- Download
SPHERE-0.1.0-arm64.dmgfrom the latest release - Open the DMG and drag SPHERE to your Applications folder
- Launch SPHERE and enter your license key when prompted
SPHERE produces two independent scores for every synthetic dataset:
| Score | What it measures |
|---|---|
| Fidelity | How closely the synthetic data reproduces the statistical properties of the real data — means, variances, correlations, and marginal distributions — on a 0–100 scale |
| Privacy | How resistant the synthetic data is to singling-out, linkability, and inference attacks, normalised against a baseline so that 100 means no measurable excess risk |
For pipelines, HPC environments, or scripting, the SPHERE algorithm is also available as a standalone command-line tool:
npm install -g sphere-cli
sphere generate real.csv -o synth.csv
sphere evaluate real.csv synth.csv→ sphere-cli on GitHub · sphere-cli on npm
Copyright © 2026 Zihuai He, Stanford University. All rights reserved.