Format, validate or minify JSON without changing its values

Strict JSON has a small set of syntax rules

JSON requires double-quoted object names and strings. Comments and trailing commas are not part of its grammar. Values such as NaN and Infinity are not JSON numbers. A syntax validator can reject those inputs, but it cannot know whether a field has the value your application expects.

Reference: RFC 8259: JSON grammar and interoperability

Choose the operation you need

JSON Formatter uses two-space indentation. JSON Validator reports a syntax result without treating it as a schema check. JSON Minifier removes whitespace outside values while preserving content inside strings. The workspace reports an error position so you can fix the input and try again.

Large numeric literals stay as written

The formatter and minifier work on the source text instead of parsing numbers into JavaScript Number values and serializing them again. This avoids rounding a long numeric identifier during formatting. It does not guarantee that another application will preserve that number when it reads the output.

The viewer is an inspection aid

The JSON input limit is 5 MiB. Tree previews have additional node, depth and displayed-value limits to keep the interface usable; a truncated tree does not mean the source was shortened. Check the full formatted output when you need the complete content, and use a schema validator separately when application-level validation is required.