JSONMASTER – Instant JSON fixing, formatting, and visualization

Summary: JSONMASTER is a free online tool that fixes, formats, validates, and visualizes JSON and related data formats directly in the browser. It supports JSON repair with AI, conversion between JSON, YAML, CSV, and XML, and provides detailed error messages with line numbers.

What it does

It validates, formats, repairs, and visualizes JSON and converts between JSON, YAML, CSV, and XML. The tool uses AI to fix broken JSON and shows human-readable errors with exact line numbers.

Who it's for

Developers and data professionals needing to validate, format, convert, or debug JSON and related data formats quickly.

Why it matters

It simplifies identifying and fixing JSON errors while preserving data privacy by running entirely in the browser.