How do I validate JSON online for free?

Visit tools-online.app/tools/json, paste your JSON data into the editor, and the tool automatically validates syntax in real-time. Click 'Load Schema' to validate against JSON Schema specifications. Errors display with line numbers instantly.

What is JSON Schema validation?

JSON Schema validation checks if JSON data matches predefined rules for structure, data types, required fields, and value constraints. It prevents API errors by ensuring data conforms to expected formats before processing.

Can I validate JSON with comments?

Yes. The validator accepts JSON5 format with comments and trailing commas as input, then exports standard RFC 8259 compliant JSON for production use.

How do I fix JSON validation errors?

The validator highlights errors with line numbers. Common fixes: add missing commas, close brackets, quote property names, remove trailing commas in standard JSON, and match data types to schema requirements.

Is online JSON validation secure?

Yes. All validation happens locally in your browser. No JSON data is uploaded to servers, ensuring complete privacy for sensitive API responses and configuration files.

Can I validate large JSON files?

Yes. The validator handles files up to several MB efficiently. Use the 'Open JSON' button to load large files directly from your computer for better performance.

How to Validate JSON Online Free - JSON Schema Validation Guide 2025

JSON validation errors crash APIs, break deployments, and waste debugging time. One missing comma or mismatched brace triggers runtime failures in production systems.

This guide shows how to validate JSON online instantly using browser-based tools that check syntax, enforce schemas, and detect errors before production. Learn to validate API responses, configuration files, and data structures with real-time feedback—no installations required.

What is JSON
Why Validate JSON
Real-World JSON Validation Examples
Why Use tools-online.app JSON Validator
How to Validate JSON: Step-by-Step
Understanding JSON Specification (RFC 8259)
Fixing Common JSON Errors
JSON5 vs Standard JSON
JSON Best Practices
Privacy & Security Guarantee
Related Data Tools

What is JSON

JSON (JavaScript Object Notation) is a lightweight, text-based data interchange format that's human-readable and machine-parseable. Originally derived from JavaScript, JSON has become the universal standard for data exchange between web applications, APIs, configuration files, and databases.

JSON represents data using key-value pairs, arrays, and nested objects. Despite its JavaScript origins, JSON is language-independent and supported by virtually every modern programming language including Python, Java, C#, PHP, Ruby, and Go.

Basic JSON structure:

Objects: Enclosed in curly braces {}
Arrays: Enclosed in square brackets []
Strings: Enclosed in double quotes ""
Numbers: Integer or floating-point
Booleans: true or false
Null: null value

Why Validate JSON

JSON powers modern APIs, configuration files, and data exchange. Invalid JSON causes API 400 errors, configuration failures, and silent data loss.

What Validation Checks

Syntax validation:

Properly closed brackets {} and arrays []
Correct comma placement
Quoted property names
Valid escape sequences
Proper number formats

Schema validation:

Required fields present
Data types match specifications
Value constraints enforced
Nested structure compliance

According to API testing research, 32% of API failures stem from malformed data—preventable with validation. For comparing JSON files, see JSON Compare Tool.

Real-World JSON Validation Examples

Example 1: API Response Validation (Production Experience)

Scenario: A production API returned malformed JSON, causing 500 errors for 15 minutes before detection.

The Problem:

{
  "users": [
    {"id": 1, "name": "Alice"},
    {"id": 2, "name": "Bob",}
  ]
}

Error: Trailing comma after "Bob" caused parsing failures in strict JSON parsers.

How We Detected It:

Copied error logs from production monitoring (New Relic)
Pasted JSON into validator at tools-online.app/tools/json
Error highlighted instantly: "Unexpected token } at line 4, column 30"
Removed trailing comma, validated clean with ✓ green checkmark
Deployed fix in 2 minutes via hot patch

Impact:

Downtime: 15 minutes
Affected users: ~2,500 API calls failed
Detection time: 12 minutes manually debugging logs
Fix time: 2 minutes after validation identified exact issue

Lesson Learned: Always validate JSON before deployment, even for "simple" config changes. A 10-second validation check would have prevented 15 minutes of downtime.

Example 2: Configuration File Migration

Real Scenario: Migrating 50+ microservice configs from development to production environment.

Challenge:

50 config.json files across different services
Team members with varying JSON experience
Zero tolerance for config errors in production

Process:

Exported all configs from dev environment using automation script
Batch validation approach:
- Opened each config in JSON validator
- Used keyboard shortcuts (Ctrl+V, visual scan, Ctrl+W) for rapid checking
Found 3 critical issues:
- Service A: Unquoted property names (JavaScript habit from developer)
- Service B: Missing comma between array elements
- Service C: Trailing comma in environment variables object
Fixed all instances before production deployment
Zero config-related incidents post-deployment

Metrics:

Time spent validating: 45 minutes for 50 files
Issues found: 3 critical, 7 formatting inconsistencies
Time saved: ~4 hours of debugging prevented
Production incidents avoided: At least 3 service failures

Team Feedback:

"The validator caught errors our code reviews missed. Having line numbers made fixes instant." — DevOps team lead

Why Use tools-online.app JSON Validator

Try JSON Validator Now →

The JSON Validator on tools-online.app provides real-time validation with syntax highlighting, schema checking, and AI-powered assistance.

JSON Validator Interface

Key Features

Top Action Bar:

Share - Generate shareable validation links for team collaboration
Open JSON - Upload files directly from computer (supports drag-and-drop)
Load Schema - Import JSON Schema for structural validation
Sample JSON - Load example data to explore features
Format - Auto-beautify with proper indentation (2-space or 4-space)
Convert to YAML - Transform to YAML format instantly
Export - Download validated JSON to local file

Editor Panel:

Line numbers - Pinpoint error locations instantly
Syntax highlighting - Color-coded keys (blue), values (green), brackets (gray)
Auto-completion - Property name suggestions as you type
Error indicators - Red underlines with hover descriptions explaining issues
Keyboard shortcuts:
- Undo: Ctrl+Z / Cmd+Z
- Redo: Ctrl+Shift+Z / Cmd+Shift+Z
- Search: Ctrl+F / Cmd+F
- Format: Ctrl+Shift+F / Cmd+Shift+F

Validation Modes:

Real-time validation - Instant error detection as you type (updates every 300ms)
Schema validation - Check against JSON Schema Draft 2020-12 rules
JSON5 support - Accept comments and trailing commas in input, export standard JSON

How to Use AI for JSON Validation

Step 1: Setup AI Integration (One-Time)

Get your API key from AIML API
Click "Settings" icon (located lower left corner of any tools-online.app tool)
Paste API key and save

Step 2: Open AI Chat

Click the AI Chat button (located lower left)
Choose "Generate" mode from dropdown

Step 3: Use Natural Language Commands

AI Generation Examples:

"Convert this JSON to YAML format"
"Generate JSON schema for user registration API"
"Fix JSON validation errors in this configuration"
"Create sample JSON data for product catalog with 5 products"
"Transform this CSV data to JSON array of objects"
"Explain why this JSON is invalid and provide corrected version"

AI Capabilities:

Format Conversion - JSON ↔ YAML, CSV, XML transformation
Schema Generation - Create validation schemas from example data
Error Analysis - Explain validation errors in plain English and suggest fixes
Data Generation - Create realistic test JSON for APIs and databases
Structure Optimization - Improve JSON organization for performance and readability

Real Example:

You: "This JSON has errors, fix it: {name: 'John', age: 30,}"

AI Response:
"The JSON has 2 errors:
1. Property names must be quoted with double quotes
2. Trailing comma after last element

Corrected version:
{
  "name": "John",
  "age": 30
}"

Understanding JSON Specification (RFC 8259)

Why Commas Matter: Deep Dive

JSON's comma rules aren't arbitrary—they're designed for streaming parsers and forward compatibility.

Technical Explanation:

When a JSON parser reads data, it uses commas as separators to know when one value ends and another begins. The parser operates in states:

State 1: Expect key or closing brace
State 2: After key, expect colon
State 3: After colon, expect value
State 4: After value, expect comma or closing brace

Trailing commas break this contract:

{"key": "value",}

The parser sees the comma and enters State 1, expecting another key-value pair. Finding } instead causes:

Streaming parsers to buffer unnecessarily waiting for next key
Strict parsers to throw SyntaxError: Unexpected token }
Lenient parsers (like JavaScript) to accept it, causing cross-language incompatibility

Historical Context:

JavaScript allowed trailing commas in objects starting with ES5 (2009), leading developers to mistakenly include them in JSON. But JSON ≠ JavaScript—JSON is a standalone specification designed for language-independent data exchange.

Why JSON remains strict:

Interoperability: Python, Java, C#, Ruby all expect strict JSON
Streaming: APIs send JSON in chunks; ambiguity breaks streaming
Forward compatibility: Strict rules prevent future parsing ambiguities

Related: See RFC 8259 Section 2 for formal grammar specification.

JSON vs JSON5: When to Use Each

JSON (RFC 8259):

Use for:

Public APIs and web services
Configuration files loaded by multiple languages
Database exports and imports
Message queue payloads
Mobile app data synchronization

Guarantees:

Works in every programming language with standard library
Streaming-safe for large datasets
No parsing ambiguity

JSON5:

Use for:

Human-edited configuration files in development
Internal tooling where only JavaScript/Node.js is used
Documentation examples requiring inline comments
Development-only files never sent over network

Features:

// single-line comments
/* */ multi-line comments
Trailing commas allowed
Unquoted object keys (when valid identifiers)
Single quotes for strings
Multi-line strings with \

Example Workflow:

Development Environment:
├── config.dev.json5  (with comments explaining each option)
│   {
│     // Database connection
│     database: {
│       host: 'localhost',  // Dev database
│       port: 5432,
│     },
│   }
│
↓ Build Process (Webpack/Rollup/Vite)
│
Production Environment:
├── config.prod.json  (comments stripped, strict compliance)
    {
      "database": {
        "host": "prod-db.example.com",
        "port": 5432
      }
    }

Tools-online.app Approach:

Our validator accepts JSON5 as input for editing convenience but always validates and exports standard JSON for production safety. Best of both worlds.

How to Validate JSON: Step-by-Step

Method 1: Paste JSON Directly

Step 1: Visit tools-online.app/tools/json

Step 2: Paste your JSON into the editor

Use Ctrl+V / Cmd+V to paste
Or drag-and-drop a .json file directly into editor

Step 3: Validation happens automatically

✅ Valid JSON: Clean syntax highlighting, no errors, green status
❌ Invalid JSON: Red underlines with error descriptions

Step 4: Review error details

Hover over red underlines for specific error messages
Line numbers show exact error location
Click error to jump to problematic line

Example Error Display:

Line 4, Column 30: Unexpected token }
Expected: property name or '}'
Found: trailing comma before '}'

Method 2: Upload JSON Files

Step 1: Visit tools-online.app/tools/json and click "Open JSON" button in top toolbar

Step 2: Select file from computer

Supports .json files
Also accepts .txt files containing JSON
Maximum recommended size: 10MB (larger files work but may be slower)

Step 3: File loads into editor with instant validation

Step 4: Make edits if needed, download corrected version

Method 3: Load Sample JSON

Step 1: Visit tools-online.app/tools/json and click "Sample JSON" button

Step 2: Explore pre-loaded example showing:

Nested objects and arrays
Different data types (string, number, boolean, null)
Proper formatting and structure

Step 3: Modify sample to learn validation behavior

Try adding trailing comma → see error
Remove quotes from key → see error
Fix errors to understand corrections

Method 4: Schema Validation

Step 1: Visit tools-online.app/tools/json and click "Load Schema" button.

Step 2: Paste your JSON Schema definition

Example Schema:

{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "type": "object",
  "required": ["id", "email"],
  "properties": {
    "id": {"type": "integer"},
    "email": {"type": "string", "format": "email"},
    "age": {"type": "integer", "minimum": 0}
  }
}

Step 3: Validator checks your JSON against schema rules

Missing required fields flagged
Type mismatches highlighted
Constraint violations explained

Fixing Common JSON Errors

Understanding proper JSON format and common errors helps debug validation issues quickly. Here's how to identify and fix the most frequent JSON problems:

Proper JSON Format Requirements

Valid JSON must follow these rules:

Property names must be quoted with double quotes
String values must use double quotes (not single)
No trailing commas after last element
All brackets and braces must be properly closed
No comments allowed in standard JSON
Numbers cannot have leading zeros (except 0.x)

Common Error Types and Solutions

1. Missing Commas

❌ Incorrect:

{
  "name": "John"
  "age": 30
}

✅ Correct:

{
  "name": "John",
  "age": 30
}

Error Message: Expected ',' or '}' after property value

2. Trailing Commas

❌ Incorrect:

{
  "users": ["Alice", "Bob",],
  "count": 2,
}

✅ Correct:

{
  "users": ["Alice", "Bob"],
  "count": 2
}

Error Message: Unexpected token ] (or }) after comma

3. Unquoted Property Names

❌ Incorrect:

{
  name: "John",
  age: 30
}

✅ Correct:

{
  "name": "John",
  "age": 30
}

Error Message: Expected double-quoted property name

4. Single Quotes Instead of Double

❌ Incorrect:

{
  'name': 'John',
  'city': 'New York'
}

✅ Correct:

{
  "name": "John",
  "city": "New York"
}

Error Message: Unexpected token '

5. Unclosed Brackets/Braces

❌ Incorrect:

{
  "users": [
    {"name": "Alice"},
    {"name": "Bob"
  ]
}

✅ Correct:

{
  "users": [
    {"name": "Alice"},
    {"name": "Bob"}
  ]
}

Error Message: Expected '}' to close object at line X

6. Invalid Escape Sequences

❌ Incorrect:

{
  "path": "C:\users\documents",
  "message": "Line 1
Line 2"
}

✅ Correct:

{
  "path": "C:\\users\\documents",
  "message": "Line 1\nLine 2"
}

Valid Escape Sequences:

\" - Double quote
\\ - Backslash
\/ - Forward slash
\n - Newline
\r - Carriage return
\t - Tab
\uXXXX - Unicode character

7. Leading Zeros in Numbers

❌ Incorrect:

{
  "id": 001,
  "version": 01.5
}

✅ Correct:

{
  "id": 1,
  "version": 1.5
}

Error Message: Unexpected number format with leading zero

Debugging Tips

Use line numbers to locate errors quickly (left margin of editor)
Check bracket pairing by clicking on bracket to highlight its pair
Validate incrementally when building large JSON structures (validate every 20-30 lines)
Copy-paste into validator before using JSON in production code
Use auto-formatting (Ctrl+Shift+F) to spot structural issues—improperly formatted code often indicates syntax errors

JSON5 vs Standard JSON

The validator supports JSON5 for editing convenience but exports standard JSON for production compatibility.

JSON5 Features (Input)

✅ Comments - // single-line and /* */ multi-line ✅ Trailing commas - After last array element or object property ✅ Unquoted keys - When keys are valid JavaScript identifiers ✅ Single quotes - For string values ✅ Multi-line strings - Using backslash line continuators

JSON5 example:

{
  // User configuration
  name: 'John Doe',
  roles: ['admin', 'editor',], // trailing comma OK
  bio: "Multi-line \
        string content",
}

Standard JSON (Output)

❌ No comments - Removed during export ❌ No trailing commas - Stripped automatically ❌ Quoted keys required - All property names in double quotes ❌ Double quotes only - Single quotes converted to double

Standard version (exported):

{
  "name": "John Doe",
  "roles": ["admin", "editor"],
  "bio": "Multi-line string content"
}

Why Support Both?

Edit with JSON5 - More forgiving, better for human editing, allows documentation via comments
Export RFC 8259 JSON - Guaranteed compatibility with all languages, APIs, and systems

Workflow:

1. Paste/edit JSON5 (with comments for documentation)
2. Validator shows structure with comments visible
3. Click "Export" or "Format"
4. Download strict JSON ready for production

JSON Best Practices

1. Always Validate Before Production

Why: Prevents runtime errors and API failures that cost time and money.

Implementation:

Validate all JSON before API deployment
Check configuration files before service restart
Test JSON in staging environments with real parsers
Integrate validation into CI/CD pipelines (GitHub Actions, GitLab CI)

Example CI/CD Integration:

# .github/workflows/validate.yml
name: Validate JSON
on: [push, pull_request]
jobs:
  validate:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - name: Validate JSON configs
        run: |
          for file in configs/*.json; do
            echo "Validating $file"
            jq empty "$file" || exit 1
          done

2. Use Consistent Naming Conventions

camelCase for JavaScript/APIs:

{
  "firstName": "John",
  "lastName": "Doe",
  "phoneNumber": "+1-555-0123"
}

snake_case for Python/databases:

{
  "first_name": "John",
  "last_name": "Doe",
  "phone_number": "+1-555-0123"
}

Pick one convention and stick to it across your entire system. Mixing conventions causes confusion and increases bug likelihood.

3. Implement Schema Validation

Define schemas for all JSON structures:

{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "type": "object",
  "required": ["id", "email"],
  "properties": {
    "id": {
      "type": "integer",
      "minimum": 1,
      "description": "Unique user identifier"
    },
    "email": {
      "type": "string",
      "format": "email",
      "description": "User email address"
    },
    "profile": {
      "type": "object",
      "properties": {
        "age": {
          "type": "integer",
          "minimum": 0,
          "maximum": 150
        },
        "country": {
          "type": "string",
          "minLength": 2,
          "maxLength": 2,
          "pattern": "^[A-Z]{2}$"
        }
      }
    }
  }
}

Benefits:

Catch data errors before they reach application logic
Self-documenting API contracts
Enable automatic validation in CI/CD
Prevent invalid data from entering databases

4. Handle Null Values Properly

Be explicit about nullable fields:

{
  "name": "John Doe",
  "middleName": null,
  "avatar": null,
  "preferences": {
    "theme": "dark",
    "notifications": true
  }
}

Design Decision: Decide whether to include null values or omit fields entirely. Both are valid but should be consistent across your API:

Include nulls: Explicit about which fields exist but have no value
Omit fields: Smaller payload, but consumers must handle missing keys

5. Use Proper Data Types

Avoid stringly-typed data:

❌ Incorrect:

{
  "age": "30",
  "isActive": "true",
  "balance": "1234.56",
  "createdAt": "1640995200000"
}

✅ Correct:

{
  "age": 30,
  "isActive": true,
  "balance": 1234.56,
  "createdAt": "2022-01-01T00:00:00Z"
}

Type Guidelines:

Numbers: Use native JSON numbers, not strings
Booleans: Use true/false, not "true"/"false" or 1/0
Dates: Use ISO 8601 format: "2025-01-29T10:30:00Z"
IDs: Numbers for database IDs, strings for UUIDs

6. Optimize for Readability

Use meaningful property names:

❌ Unclear:

{
  "u": "john_doe",
  "e": "john@example.com",
  "c": 1641234567
}

✅ Clear:

{
  "username": "john_doe",
  "email": "john@example.com",
  "createdTimestamp": 1641234567
}

Naming Guidelines:

Use full words, not abbreviations (except common ones like id, url)
Be descriptive: userRegistrationDate vs date
Avoid ambiguity: isActive vs active (is it boolean or string?)

7. Version Your JSON Schemas

Include version information in API responses:

{
  "schemaVersion": "1.2.0",
  "apiVersion": "v1",
  "data": {
    "user": {
      "id": 123,
      "name": "John Doe"
    }
  }
}

Why Version?

Track API evolution over time
Enable backward compatibility detection
Help consumers understand which fields to expect
Facilitate schema migration strategies

8. Implement Error Handling

Structure error responses consistently:

{
  "success": false,
  "error": {
    "code": "VALIDATION_ERROR",
    "message": "Invalid email format",
    "field": "email",
    "details": {
      "received": "john@invalid",
      "expected": "valid email address"
    },
    "timestamp": "2025-01-29T10:30:00Z"
  }
}

Standard Error Fields:

code - Machine-readable error identifier
message - Human-readable description
field - Which input caused the error (for forms)
details - Additional context for debugging
timestamp - When error occurred (for log correlation)

9. Use Arrays Consistently

Prefer arrays over numbered properties:

❌ Avoid:

{
  "item1": "apple",
  "item2": "banana",
  "item3": "cherry"
}

✅ Prefer:

{
  "items": ["apple", "banana", "cherry"]
}

Why?

Easier to iterate programmatically
Variable length without schema changes
Standard array methods in all languages

10. Secure Sensitive Data

Never include sensitive information in JSON:

❌ Dangerous:

{
  "username": "john_doe",
  "password": "secret123",
  "apiKey": "abc-def-ghi-jkl",
  "creditCard": "4111-1111-1111-1111"
}

✅ Secure:

{
  "username": "john_doe",
  "tokenHash": "$2a$12$KIXxPz...",
  "expiresAt": "2025-01-30T10:30:00Z"
}

Security Rules:

Store passwords as bcrypt/argon2 hashes, never plaintext
Use tokens with expiration instead of API keys in responses
Mask credit cards: "4111********1111"
Never log JSON containing PII or credentials

Privacy & Security Guarantee

Client-Side Processing Only

Your JSON Never Leaves Your Browser:

✅ All validation happens locally using JavaScript ✅ Zero server uploads or cloud storage ✅ No logging, tracking, or data retention ✅ Works offline once page loads

Technical Implementation:

// Validation runs entirely in browser
function validateJSON(text) {
  try {
    JSON.parse(text);  // Uses native browser API
    return { valid: true };
  } catch (error) {
    return { 
      valid: false, 
      error: error.message,
      line: error.lineNumber 
    };
  }
}

Proof of Client-Side Processing:

Open browser DevTools (F12)
Go to Network tab
Paste JSON and validate
Result: Zero network requests during validation

Why We Chose Client-Side:

Many JSON validators upload your data to servers for processing. We deliberately chose client-side processing to guarantee privacy, even at the cost of some advanced features (like validating against remote schemas without CORS).

Security Best Practices

Safe for Sensitive Data:

✅ API keys in config files ✅ Database connection strings ✅ Internal service credentials ✅ Customer data exports ✅ Financial transaction logs ✅ Healthcare/HIPAA data (PHI)

No Data Collection:

❌ We don't store your JSON ❌ We don't analyze your content ❌ We don't train AI models on your data ❌ We don't track usage patterns per user

HTTPS Encryption:

All traffic encrypted via TLS 1.3
Certificate: Let's Encrypt (auto-renewed every 90 days)
A+ rating on SSL Labs Test
HSTS enabled (HTTP Strict Transport Security)

Transparent Operation

Open About Limitations:

Maximum file size: Limited by browser memory (typically 100MB+)
JSON5 support: Input only, exports standard JSON for compatibility
Browser compatibility: Works in Chrome 90+, Firefox 88+, Safari 14+, Edge 90+
Schema validation: Supports JSON Schema Draft 2020-12

No Hidden Features:

No account required (no email collection)
No tracking cookies or analytics pixels
No advertisements or upsells
No feature paywalls—everything is 100% free

Validate Other Formats

YAML Validator - Kubernetes, Docker configs with real-time syntax checking
SQL Formatter - Database queries with syntax highlighting
PostgreSQL Editor - Test database schemas and JSON columns

Convert Between Formats

JSON to YAML Converter - Transform for Kubernetes deployment files
YAML to JSON Converter - Process YAML configs in JSON-compatible systems
Markdown Editor - Document JSON APIs and data structures

Compare & Analyze Data

JSON Compare Tool - Detect file differences with semantic analysis
YAML Compare Tool - Compare configuration changes across environments
Code Compare Tool - Compare API handler code

Complete Tool Collections

Browse by Category:

Online Data Tools - Complete data processing and validation toolkit
Online Code Tools - Development environment with 15+ programming languages
Online Compare Tools - File and code comparison suite
Online Web Tools - Web development utilities
Online Productivity Tools - Workflow optimization tools

Learn More & Guides

Educational Resources:

How to Compare Data Files Without Installing Software - Data comparison best practices
Browser-Based Tools vs Desktop Apps - Platform comparison guide
Essential Online Utilities Checklist for Developers 2025 - Complete developer toolkit

External Standards & References

JSON Specification (RFC 8259) - Official JSON standard from IETF
JSON Schema Documentation - Schema validation reference and specifications
MDN Web Docs - JSON - JavaScript JSON API documentation
JSON5 Specification - Extended JSON format with comments and relaxed syntax

Discover More: Visit tools-online.app to explore our complete suite of browser-based development tools.

Validate Your JSON Now

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Categories

Tags

How to Validate JSON Online Free - JSON Schema Validation Guide 2025

Table of Contents

What is JSON

Why Validate JSON

What Validation Checks

Real-World JSON Validation Examples

Example 1: API Response Validation (Production Experience)

Example 2: Configuration File Migration

Why Use tools-online.app JSON Validator

Key Features

How to Use AI for JSON Validation

Understanding JSON Specification (RFC 8259)

Why Commas Matter: Deep Dive

JSON vs JSON5: When to Use Each

How to Validate JSON: Step-by-Step

Method 1: Paste JSON Directly

Method 2: Upload JSON Files

Method 3: Load Sample JSON

Method 4: Schema Validation

Fixing Common JSON Errors

Proper JSON Format Requirements

Common Error Types and Solutions

Debugging Tips

JSON5 vs Standard JSON

JSON5 Features (Input)

Standard JSON (Output)

JSON Best Practices

1. Always Validate Before Production

2. Use Consistent Naming Conventions

3. Implement Schema Validation

4. Handle Null Values Properly

5. Use Proper Data Types

6. Optimize for Readability

7. Version Your JSON Schemas

8. Implement Error Handling

9. Use Arrays Consistently

10. Secure Sensitive Data

Privacy & Security Guarantee

Client-Side Processing Only

Security Best Practices

Transparent Operation

Related Data Tools

Validate Other Formats

Convert Between Formats

Compare & Analyze Data

Complete Tool Collections

Learn More & Guides

External Standards & References

Validate Your JSON Now