JSON Formatter & Validator
Paste any JSON and instantly format, validate, and explore it. Our JSON Formatter features syntax highlighting, interactive tree view, error detection with line numbers, and minify/beautify toggle. Works entirely in your browser — no data sent to servers.
Input JSON
Output · 14 lines · 216 chars
{
"name": "ToolNest",
"version": "1.0.0",
"tools": [
"JSON Formatter",
"EMI Calculator",
"Regex Tester"
],
"premium": false,
"meta": {
"author": "ToolNest Team",
"license": "MIT"
}
}JSON Structure
Valid JSON must:
- Start with { } (object) or [ ] (array)
- Use double-quoted string keys
- Use valid value types: string, number, boolean, null, object, array
- No trailing commas
- No commentsExamples
Format minified JSON
Result: Beautifully indented 4-space formatted JSON
Paste any minified JSON to get a readable formatted version.
Validate invalid JSON
Result: Error: Unexpected token } at line 1, col 30
Trailing comma detected — exact error location highlighted.
Explore nested JSON
Result: Interactive tree: users > [0] > id, name; [1] > id, name
Tree view lets you collapse/expand nested structures.
Frequently Asked Questions
Is my JSON data safe?
Absolutely. All processing happens 100% in your browser using JavaScript. Your JSON data never leaves your device or gets sent to any server.
What is the maximum JSON size I can format?
Our tool handles JSON files up to 10MB without issues. For larger files, consider processing them in chunks.
Can I validate JSON Schema?
Currently the tool validates JSON syntax. JSON Schema validation (draft-07/2019-09) is on our roadmap.
What is the difference between JSON and JSON5?
JSON5 is an extension that allows comments, trailing commas, and unquoted keys. Our formatter handles standard JSON (RFC 8259).
Can I convert between JSON and other formats?
Yes! Use our JSON to CSV, JSON to XML, or CSV to JSON tools for format conversion.