Privacy-first architecture
How DuckViz keeps your raw data inside your browser.
DuckViz processes your data files entirely in the browser. The data engine is DuckDB-WASM, running inside a Web Worker. Charts are rendered locally with D3. State is persisted to IndexedDB so you can close the tab and come back.
What stays in the browser
- Raw cell values from every CSV / Excel / JSON / XML / log file you upload.
- SQL query results.
- DuckDB tables (persisted as Parquet in IndexedDB).
- Dashboard layouts, widget configs, and report content.
What goes to our servers
Only schema-level metadata is sent to AI providers:
- Column names and data types.
- Detected domain and format hints.
- A small sample (up to 10 lines) of log file text — solely to detect the log format. Never used again after detection.
- The DuckDB SQL queries the AI generates for your charts.
Actual row-level values never leave your browser.
Authentication & accounts
Email and display name are stored in Supabase. Payments (one-time credit packs) are handled by our payment processor — we never see full card details.
Clearing local data
- Upload → Start fresh wipes the persisted session (tables, files, state).
- The Memory badge in the header lets you unmount individual tables.
Read the full Privacy Policy for the legal version.