JSON Tools
A complete toolkit for working with JSON data. Format, validate, repair, compare, escape, and generate schemas — all free and 100% private in your browser.
Beautify and pretty print JSON with configurable indentation
Query, filter, and explore JSONPath with an interactive tree — click any node for its path
Validate JSON syntax in real time with error detection
Explore JSON structure with an interactive tree view
Auto-fix malformed JSON — trailing commas, single quotes, missing brackets
Side-by-side diff viewer for two JSON objects
Escape and unescape JSON strings for APIs and code
Convert JSON objects to escaped strings and back
Generate TypeScript Zod schemas from JSON instantly
Parse escaped and stringified JSON strings
Understand JSONPath expressions in plain English — filters, recursion, K8s
Convert YAML to JSON and JSON to YAML for configs and APIs
Decode JWT header, payload, and expiration locally
Why use our JSON tools?
FormatList's JSON toolkit is designed for modern developers who work with APIs, AI models, and configuration files. Every tool is optimized for speed, privacy, and ease of use.
Built for AI workflows
- Repair JSON from ChatGPT, Claude, and Gemini output automatically.
- Extract JSON from markdown code blocks in AI responses.
- Generate Zod schemas from AI-generated sample data.
Developer-focused features
- Monaco Editor with syntax highlighting and line numbers.
- Real-time validation and error detection.
- Side-by-side diff comparison for debugging.
- 100% client-side — zero data upload.
JSON Tools FAQ
Are these JSON tools free?
Yes. All JSON tools on FormatList are 100% free with no signup, no ads, and no usage limits.
Is my JSON data sent to a server?
No. All processing happens locally in your browser using JavaScript. Your data never leaves your computer.
Can I use these tools for AI-generated JSON?
Yes. Our JSON Repair and JSON Formatter tools handle common issues in AI model output like trailing commas and single quotes.
Do you support large JSON files?
Yes. The tools use Monaco Editor under the hood, which efficiently handles large files. Performance depends on your browser and device.