JSON Validator & Syntax Linter

Validate JSON syntax with line and column error indicators, calculate structural tree metrics, and format or minify payloads instantly.

Input JSON Payload

Syntax Status
Valid JSON

Keys

13

Objects

4

Arrays

3

Max Depth

5

Processed Output Preview443 chars
{
  "company": "Softzar",
  "domain": "https://softzar.com/",
  "active": true,
  "tools": [
    {
      "slug": "json-validator",
      "category": "developer",
      "features": ["validation", "formatting", "minification"]
    },
    {
      "slug": "slug-generator",
      "category": "text",
      "features": ["seo", "bulk mode", "normalization"]
    }
  ],
  "metadata": {
    "updatedAt": "2026-03-29",
    "owner": "Softzar Team"
  }
}

Zero Server Upload Privacy

JSON documents and API keys are parsed entirely inside local browser memory.

RFC 8259 Context-Free Grammar & Tree Depth Equations

Standard JSON parsing evaluates recursive context-free grammar rules to validate document syntax:

1. Formal JSON Grammatical Production Rule
JSON-Text = ws · (Object | Array) · ws,   Value = Object | Array | String | Number | true | false | null
2. AST Structural Nesting Depth Formula
MaxDepth(N) = 1 + max_{c ∈ Children(N)} MaxDepth(c)
Step-by-Step Lexical Analysis & Recursive Descent Breakdown
Step 1: Character Stream Tokenization
Scan literals, string delimiters ("), braces ({}), and numeric values.
Step 2: Grammar State Transition Verification
Ensure keys have double quotes and trailing commas are omitted.
Step 3: Syntax Verification Verdict
Syntax Result=Valid RFC 8259 JSON

Common JSON Syntax Failures & Resolution Reference

Syntax Error TypeInvalid ExampleValid CorrectionRule Violation
Trailing Comma{"a": 1,}{"a": 1}No trailing comma allowed before closing brace
Single Quotes{'name': 'Alex'}{"name": "Alex"}Keys and strings must use double quotes (")
Unquoted Keys{id: 101}{"id": 101}Object properties must be string literals
Comments// comment{"_comment": "..."}RFC 8259 forbids comments

Frequently Asked Questions

What does this JSON validator check?
This validator checks whether your payload complies strictly with the RFC 8259 standard. It detects missing quotes, trailing commas, unmatched brackets, invalid Unicode escapes, and malformed object keys with exact line and column error pointers.
Why do line and column error hints matter for debugging?
When working with large API payloads or configuration trees, line and column hints pinpoint the exact character where parser failure occurred, eliminating manual trial-and-error inspection.
Is formatting or indentation required for JSON to be valid?
No. Whitespace is insignificant in JSON grammar. Minified payloads without line breaks are 100% valid as long as quotes, colons, and commas conform to specification.
Is my JSON payload sent to external servers?
No. All parsing, recursive AST depth traversal, formatting, and minification execute entirely inside your local browser memory.

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