Validate JSON syntax in real time. See exact line and column of errors, common mistake hints, and structure summary. Browser-based, no upload.
Privacy: Conversion runs locally in your browser. Your source file is not uploaded to JAD Apps servers.
Catch JSON syntax errors instantly with exact line and column reporting. The validator highlights common mistakes — trailing commas, unquoted keys, single quotes, mismatched brackets — and shows a structure summary so you understand the shape at a glance.
Free is enough for most one-off jobs. Pro raises the file and batch caps; Pro + Media unlocks GB-scale streaming and unlimited duration.
Larger files supported on Developer (5 GB CSV) and Enterprise (unlimited). All processing happens in your browser — files never reach a server.
Drop a JSON file or paste text
Drag a .json file onto the dropzone or paste text. Validation runs against the native parser.
Read the result
Valid JSON shows a structure summary. Invalid JSON shows the error message and line/column where the parser failed.
Fix and re-run
Edit the source and re-validate. For complex repairs, switch to JSON Format Fixer which auto-repairs common mistakes.
Strict mode rejects technically-invalid JSON like duplicate keys, NaN/Infinity, and trailing commas. Most engines accept some of these in lenient mode.
This tool only validates syntax. To check shape against a schema, generate a schema with JSON Schema Generator and run it through any AJV-based validator.
Use JSON Format Fixer — it auto-repairs unquoted keys, trailing commas, and single quotes that JSON.parse rejects.
Privacy
Conversion runs locally in your browser. Your source file is not uploaded to JAD Apps servers.
Automatically fix common broken JSON: missing quotes on keys, trailing commas, single quotes, and unescaped characters. Browser-based, no upload.
Format and prettify JSON with 2 spaces, 4 spaces, or tabs. Sort keys alphabetically for readable diffs. Browser-based, no upload required.
Automatically generate a valid JSON Schema (Draft 7) from any JSON data sample. Infers types, required fields, and nested object shapes. No upload.