SQL Playground — 100% Local Query Tester

Drop your .sql dumps, CSVs, or JSON files to instantly explore and query your data. Powered by WebAssembly, everything runs privately on your device.

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Frequently Asked Questions

PostgreSQL, SQLite, and MySQL dumps are auto-detected. PostgreSQL runs via PGlite (WASM Postgres). SQLite and MySQL run via sql.js (WASM SQLite). MySQL uses a compatibility fallback that strips MySQL-specific syntax.

SQL Playground reads the first 1 MB of your file and runs weighted regex rules against dialect-specific markers — like pg_catalog for PostgreSQL, PRAGMA for SQLite, and ENGINE=InnoDB for MySQL. The winner is shown with a confidence percentage.

No. The file is streamed in 2 MB chunks into the WASM database engine inside a Web Worker. The main thread stays responsive even for large dumps. Only the file reference is held, not the contents.

Yes. The SQL editor supports full SQL syntax with CodeMirror highlighting. Press Cmd+Enter (or Ctrl+Enter) to execute. Results appear in a paginated table with column headers.

No. Everything — dialect detection, WASM database, query execution — runs 100% in your browser. Your .sql file never leaves your device. Zero network requests during processing.

Yes. Download results as CSV or JSON with one click. You can also copy the result set to your clipboard as tab-separated values for pasting into spreadsheets.

Yes. After import, the Schema Explorer lists all tables with column names, types, and row counts. Click any table to auto-fill a SELECT query.

Free SQL Playground — Run Queries 100% In Browser - Privacy-First, Offline Developer Tool

Global Architecture: This tool runs entirely in your browser using WebAssembly. Unlike server-side alternatives, your data (JWTs, Logs, SQL) never leaves this device. It works offline and handles massive files (1GB+) bounded only by your RAM.