MapJSON is maintained by a small team of developers who use JSON tools daily in production systems. We built the toolkit we wished existed: fast, private, and free.

Is MapJSON really free?

Yes. All core JSON utilities are free for personal and commercial use. We fund hosting through ethical advertising that does not require uploading your data.

Where is my data processed?

Entirely in your browser. JSON, CSV, YAML, and configuration inputs never leave your device when using our transformation tools.

About MapJSON

MapJSON is a suite of free, privacy-focused online tools for developers who work with JSON every day. We help you format, validate, compare, convert, and transform structured data without sending sensitive payloads to a server.

Our mission

Modern software runs on JSON—REST APIs, webhooks, configuration files, analytics events, and cloud infrastructure definitions. Developers deserve utilities that are instant, trustworthy, and safe for production data. Our mission is to provide professional-grade JSON tooling that respects privacy while remaining accessible to everyone from students to senior platform engineers.

Every tool on this site executes locally in your browser using JavaScript. That architectural choice means API keys, customer records, unreleased product configurations, and internal telemetry never transit our infrastructure. You get the convenience of an online tool with the security posture of an offline utility.

What we offer

JSON Formatter & Validator — prettify minified payloads and catch syntax errors before deployment.
JSON Diff & Mapper — compare API versions and reshape fields during integrations.
Converters — JSON to YAML, ENV, TypeScript, CSV, and back for DevOps and data workflows.
Developer guides — in-depth articles on formatting, security, API design, and debugging on our blog.

Technology

MapJSON is built with Next.js, React, and TypeScript on the frontend. Transformations use battle-tested open-source libraries where appropriate (for example YAML parsing) and custom logic tuned for developer workflows. The site is deployed on modern edge infrastructure for fast global delivery while keeping all data processing client-side.

We follow web performance best practices: static generation for content pages, minimal JavaScript on informational routes, and responsive layouts for desktop and mobile debugging sessions.

Transparency & advertising

MapJSON is supported by Google AdSense display advertising. Ads help us keep tools free and maintain infrastructure costs. Advertising partners may use cookies as described in our Privacy Policy. Tool functionality never depends on sharing your JSON with advertisers—processing remains local.

Contact the team

Questions, partnership inquiries, or bug reports? Visit our contact page or email zinlee0pro@gmail.com.

Frequently Asked Questions

Who builds MapJSON?: MapJSON is maintained by a small team of developers who use JSON tools daily in production systems. We built the toolkit we wished existed: fast, private, and free.
Is MapJSON really free?: Yes. All core JSON utilities are free for personal and commercial use. We fund hosting through ethical advertising that does not require uploading your data.
Where is my data processed?: Entirely in your browser. JSON, CSV, YAML, and configuration inputs never leave your device when using our transformation tools.