Strict JSON Validation & Linting
A single misplaced comma is enough to completely break an application. Our JSON Validator acts as a strict linter, analyzing your JSON data against the official ECMA-404 specification and pinpointing exactly where your syntax fails.
Finding the Unfindable Bug
Unlike basic built-in parsers (like JSON.parse) that throw generic "Unexpected token" errors, our tool provides actionable, human-readable feedback:
- Exact Line Pinpointing: Highlights the precise line and character number where the parser choked.
- Common Error Detection: Clearly identifies common mistakes like trailing commas, unquoted keys, single quotes instead of double quotes, and missing brackets.
- Auto-Fix Capability: For simple errors (like a trailing comma at the end of an array), the tool can automatically repair the JSON with one click.
How to Use This Tool
- Upload or Input Data: Select your file or paste your data directly into the tool interface. Everything remains on your device.
- Configure & Process: Adjust any optional settings if necessary. The tool will process your data instantly inside your browser.
- Download Result: Preview the output and click the download or copy button to save your final results.
Frequently Asked Questions
Why is my JSON invalid? It works in JavaScript!
JavaScript objects and JSON are not the same thing. JSON is a strict data format. It requires double quotes around all keys, does not allow single quotes for strings, and forbids trailing commas.
Can I validate massive JSON files?
Yes, the tool is optimized to parse files up to several megabytes quickly in the browser.
Does it validate against a JSON Schema?
This tool focuses on syntax validation (checking if the code is valid JSON). It does not currently perform structural validation against custom JSON Schemas.