Free JSON, CSV and
TypeScript developer tools.

DevWrench offers free browser-based developer tools for common JSON, CSV, TypeScript and API workflows. Use it to convert JSON, inspect large files, transform API requests and compare structured data without accounts or setup.

• Convert JSON to TypeScript interfaces in seconds for React, Next.js and TypeScript projects.
• Turn cURL commands into Fetch code without manually rewriting headers, methods and request bodies.
• Flatten nested JSON into CSV when you need spreadsheet-friendly exports from structured API responses.
• Open large CSV files directly in the browser without the lag and crashes of traditional spreadsheet tools.
• Compare two JSON objects with a readable diff viewer when debugging config, payload or schema changes.