Developer Tools
JSON Formatter & Validator
Format, beautify, minify and validate JSON instantly. Errors are reported with the exact line and column. Everything runs in your browser — your data is never uploaded.
A faster way to read and debug JSON
Whether you are inspecting an API response, debugging a failing test, or cleaning up a config file, this tool turns dense or broken JSON into something readable in one click. The validator pinpoints the exact line and column of the first syntax error, so you spend less time hunting for a missing comma or a stray bracket.
What you can do
- Format & beautify — pretty-print with 2-space, 4-space or tab indentation.
- Minify — strip whitespace to the smallest valid payload.
- Validate — catch errors with precise line and column location.
- Tree view — explore nested objects and arrays with collapsible nodes.
- Search — find any key or value inside the tree.
- Copy, download & upload — move JSON in and out without leaving the page.
Private by design
Many online formatters send your JSON to a backend server. This one does not. All parsing, formatting and validation happen locally in your browser with native JavaScript, so you can safely work with production data, API keys and personal information.
Frequently asked questions
Is this JSON formatter safe to use with private data?
Yes. The tool runs entirely in your browser using JavaScript. Your JSON is never sent to a server, logged, or stored, so it is safe to paste API responses and sensitive payloads.
What is the difference between formatting and minifying JSON?
Formatting (beautifying) adds indentation and line breaks to make JSON readable. Minifying removes all unnecessary whitespace to produce the smallest valid JSON, which is ideal for production payloads and reducing bandwidth.
Why is my JSON invalid?
Common causes are trailing commas, single quotes instead of double quotes, unquoted keys, missing commas or brackets, and comments (which standard JSON does not allow). The validator points to the exact line and column of the first error.
Is there a size limit?
There is no hard limit, but very large documents (tens of megabytes) depend on your device memory since all processing happens locally in the browser.
Testing the APIs behind that JSON?
OrbitTest writes readable, intent-first browser tests that follow real user journeys — including the login, redirect and API flows that produce this data. Open source under Apache 2.0.