Developer Tools / JSON Validator

JSON Validator & Linter

Validate JSON syntax with exact error line numbers, parse tree diagnostics, and auto-fix repairs for trailing commas and single quotes.

Validator Status

Valid RFC 8259 JSON

The document has been successfully parsed with zero syntax errors.

Root Type

object

Key Count

13 keys

Max Depth

5 levels

Data Size

0.22 KB

JSON Document10 lines • 228 characters
Runs 100% client-side in your browser.
Sealed Browser Processing

Free Browser-Based JSON Syntax Checker & Linter

Troubleshooting invalid JSON payloads and API responses in local memory

JSON (JavaScript Object Notation) is the universal lingua franca of the modern web, but its strict syntax rules frequently trip up developers. Forgetting to wrap keys in double quotes, leaving a trailing comma after the last array item, or using unescaped control characters will cause `JSON.parse` to crash.

Modifyle's JSON Validator provides instant feedback on document validity without uploading your payload to external servers. If an error is present, you receive an immediate alert indicating the exact offending line and character position.

Once valid, inspect key counts, maximum nesting depth, and overall payload size, or auto-format the payload for immediate readability.

How It Works in 3 Simple Steps

01

Enter JSON Text

Paste your raw payload or upload a .json file directly into the editor.

02

Inspect Syntax & Diagnostics

Review instant validity status, line and column error indicators, or structural tree metrics.

03

Auto-Fix or Format

Use the Auto-Fix button to correct common comma and quote errors, or click Prettify to format.

Why choose Modifyle JSON Validator?

100% Client-Side Execution (Zero file upload to external servers)
No file size or page count limits imposed by server queues
Completely free with no credit card, registration, or software install
Full privacy compliance: documents stay sealed inside your local browser memory
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