FreeDev Tools

Free Online JSON Tools

A complete collection of free, browser-based JSON utilities — format, validate, convert, compare, and transform JSON data without installing anything. All tools run locally in your browser, so your data stays private.

What are online JSON tools?

JSON (JavaScript Object Notation) is the universal data exchange format for APIs, configuration files, and web applications. Free online JSON tools help developers work with JSON data faster — formatting messy API responses, validating structure, converting to other formats, and comparing changes between two versions.

JSON Formatter & Validator

The most used tool in any developer's workflow. Paste an API response or config file and instantly see it formatted with proper indentation, color-coded syntax highlighting, and immediate validation. Invalid JSON is flagged with the exact line and character of the error.

JSON conversion tools

Our converters handle the most common format transformations: JSON to CSV for spreadsheet import, CSV to JSON for API preparation, JSON to XML for legacy system integration, XML to JSON for modernization, and JSON to YAML for Kubernetes and CI/CD configuration.

Are these tools free and private?

Yes. All JSON tools run entirely in your browser using JavaScript — no data is uploaded to any server. This makes them safe for production API keys, credentials, and sensitive configuration data.