JSON Validator

Validate JSON data and get detailed error reporting with exact error location, structure analysis, and statistics.

Drop a .json file here or browse

JSON Data:

Try examples:

Valid object Valid array Trailing comma Single quotes Unquoted key

How It Works

This tool validates your JSON using the browser's native JSON.parse(), which strictly follows the ECMA-404 standard. All processing happens entirely in your browser — no data is sent to any server.

What Gets Checked

Correct JSON syntax (brackets, braces, commas, colons)
Strings use double quotes (not single quotes)
No trailing commas after last element
All object keys are quoted strings
Valid value types: string, number, object, array, true, false, null
Proper nesting of objects and arrays

JSON Syntax Rules

Data is in key/value pairs: "key": "value"
Data is separated by commas
Curly braces hold objects: { }
Square brackets hold arrays: [ ]
Strings must use double quotes: "text"
No comments allowed
No trailing commas

Common Errors

Error	Example	Fix
Trailing comma	`{"a": 1,}`	`{"a": 1}`
Single quotes	`{'a': 1}`	`{"a": 1}`
Unquoted keys	`{a: 1}`	`{"a": 1}`
Missing comma	`{"a": 1 "b": 2}`	`{"a": 1, "b": 2}`
Undefined value	`{"a": undefined}`	`{"a": null}`

Tip: Need to format or minify your JSON? Try the JSON Formatter for additional features like pretty-printing, minification, and key sorting.

Embed This Util

You can embed this util on your own site as a widget. Adding ?embed=1 to the URL loads a compact version with just the tool itself; no header, menu, or documentation. Paste this snippet into your HTML:

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