TransformX - Free JSON to CSV & TypeScript Interface Converter

Instant, 100% client-side tool to convert JSON to CSV, TypeScript interfaces, JSON Schema, and SQL queries.

How to Convert JSON to CSV & Structured Formats

TransformX provides a frictionless, zero-upload development workspace for engineers, data analysts, and product managers. Modern web applications, REST APIs, and NoSQL databases store data in hierarchical JSON documents. However, relational databases, spreadsheet editors like Microsoft Excel and Google Sheets, and Business Intelligence (BI) pipelines require flat tabular structures (CSV or TSV).

  1. Input Your JSON Data: Paste raw JSON text into the editor, drag and drop a .json file, or click "Load Sample Data" to preview formatting.
  2. Select Target Transformation: Choose your desired output: CSV, TSV, TypeScript Interfaces, SQL DDL Schema, or JSON Schema.
  3. Configure Unpacking Rules: Toggle "Flatten Nested Objects" to automatically unpack deeply nested child properties using dot notation (e.g. user.profile.avatar_url).
  4. Export or Copy: Instantly copy the output to your clipboard or download a clean .csv or .ts file directly to your device.

Deep Object Flattening

When converting complex JSON structures to CSV, nested child objects are expanded recursively. For example, a JSON property like {"company": {"address": {"city": "Austin"}}} is automatically flattened into a column named company.address.city, ensuring zero data loss during spreadsheet exports.

Automatic TypeScript Types

TransformX scans your JSON data across all array records to detect optional fields, unions, numbers, booleans, and nullables. It generates clean, production-ready TypeScript interfaces conforming to strict mode rules for Next.js, React, and Node.js codebases.

Relational SQL Schema Generation

Migrating API payloads to PostgreSQL, MySQL, or SQLite? TransformX automatically generates CREATE TABLE statements by inspecting data values across every record. Integers map to BIGINT or INTEGER, decimal numbers map to NUMERIC(10,2), booleans map to BOOLEAN, ISO 8601 timestamps map to TIMESTAMP WITH TIME ZONE, and text values map to VARCHAR or TEXT.

Frequently Asked Questions

Is my JSON data uploaded or stored on any server?

No, absolutely not. TransformX operates 100% client-side inside your web browser. All parsing, transformation, and file downloads are executed using local JavaScript on your computer.

How does the converter handle deeply nested JSON objects and arrays?

When 'Flatten Nested Objects' is enabled, child keys are unpacked into flat column headers using clean dot notation (for instance: user.address.geo.lat).

Does the TypeScript generator support strict mode and optional properties?

Yes! TransformX analyzes your entire JSON dataset across all records. If a property is missing in certain objects or has a null value, the generator automatically marks it as optional (e.g. propertyName?: string).

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Technical Reference & Methodology Guide

JSON Serialization, CSV Flattening & TypeScript Schema Guide

How nested JSON objects and arrays are normalized into relational CSV tables and static TypeScript interfaces.

Read Engineering Guide