JSON Studio

JSON to SQL Schema

Instantly convert JSON arrays into database-ready SQL scripts. Automatically infers column data types and generates bulk INSERT statements for PostgreSQL, MySQL, and SQLite.

JSON Array Data
Paste an array of JSON objects here: e.g. [{"id": 1, "name": "Alice"}, ...]
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Generated SQL Definition & Seeder

Waiting for valid array data

Paste a JSON array containing objects to generate SQL statements.

Accelerate Database Seeding

When working with external APIs, mock data files, or JSON exports, inserting that data into a relational database can be incredibly tedious. Manually mapping JSON fields to SQL columns, figuring out the right data types, handling NULL values — it adds up fast when you've got dozens of fields and hundreds of records.

This tool automates the entire process. Paste a JSON array and get a complete SQL script with CREATE TABLE (properly typed columns) and bulk INSERT statements. Works with PostgreSQL, MySQL, and SQLite — each dialect gets the correct data types and syntax.

How Type Inference Works

The converter doesn't just look at the first record. It scans every object in your JSON array to build an accurate type map. If a field contains 42 in one record and 3.14 in another, it correctly infers a decimal type. If a value appears as null anywhere, the column becomes nullable.

Dialect-Specific Types

JSON TypePostgreSQLMySQLSQLite
IntegerINTEGERINTINTEGER
DecimalDOUBLE PRECISIONDOUBLEREAL
BooleanBOOLEANTINYINT(1)INTEGER
StringTEXTTEXTTEXT

When to Use This Tool

The most common use cases we see are seeding development databases from API exports, migrating data from NoSQL to SQL databases, and creating test fixtures from JSON mock data. Instead of writing tedious INSERT statements by hand or building custom migration scripts, you can paste, convert, and run the SQL directly.

This tool runs 100% client-side — no JSON data or database structures are ever transmitted to any server.

Frequently Asked Questions

PostgreSQL, MySQL, and SQLite. The generator uses dialect-specific data types — e.g., SERIAL for PostgreSQL auto-increment vs AUTO_INCREMENT for MySQL.
The tool scans all objects in your JSON array and detects integers, decimals, booleans, and strings. It assigns the most appropriate SQL column type for each dialect.
Yes. It generates efficient bulk INSERT blocks instead of individual statements, which databases parse and execute much faster.
Absolutely. All schema inference and SQL scripting happen locally in your browser. Your JSON records and the resulting database scripts never leave your machine.

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