verified Reliable Data Validation

Validators

Validate syntax, structure and correctness of your data. Professional-grade tools that check JSON, XML, YAML, HTML and more against standards with detailed error reporting.

Start Validating arrow_forward

JSONXMLYAMLHTML

validation-result.json

{
  "valid": false,
  "errors": [
    {
      "line": 12,
      "pos": 15,
      "msg": "Unexpected '}'"
    },
    {
      "line": 25,
      "msg": "Missing 'email'"
    }
  ]
}

Validator Tools

Comprehensive validation engines for every data format.

data_object

JSON Validator

Validate JSON syntax and structure with detailed error reporting

code

XML Validator

Validate XML syntax and well-formedness

settings_ethernet

CSS Validator

Validate CSS syntax and structure

search_insights

Regex Tester

Test and validate regular expressions with examples

mail

Email Validator

Validate email address syntax, format and deliverability

verified

JSON Schema Validator

Validate JSON data against a JSON Schema

How to Use

Paste Your Data

Copy your JSON, XML, YAML, CSS, HTML or other structured data and paste it into the input area of your chosen validator tool.

Validate Instantly

Our engine parses your data and checks it against format-specific rules. Get immediate feedback with detailed line-by-line error reporting in milliseconds.

Fix & Export

Review detailed error messages with exact line and column positions, fix issues directly, and export clean, validated data for your workflow.

What Are Data Validators?

Data validators are tools that check the syntactic and semantic correctness of structured data. They ensure that your JSON, XML, YAML, and other data formats conform to specific standards before processing. Unlike formatters that change presentation, validators verify correctness and help you catch errors early in the development cycle.

check_circleSyntax Checking

check_circleSchema Validation

check_circleError Localization

check_circleFormat Compliance

Benefits of Using Validators

bug_report

Early Error Detection

Identify syntax errors instantly with precise line and column information, catching issues before they cause runtime failures in your application.

verified

Data Quality Assurance

Ensure your API payloads, configuration files, and datasets are well-formed and conform to expected standards before deployment.

schedule

Save Development Time

Quick validation without complex setup or environment configuration. Catch malformed data early and reduce debugging time in CI/CD pipelines.

Secure & Comprehensive Validation

Your data stays private while we deliver thorough, multi-level validation.

shield

Client-Side Processing

All validation runs entirely in your browser. No data is transmitted to external servers, ensuring maximum privacy and security.

bolt

Instant Results

Zero latency. Get immediate validation feedback even with large files, powered by high-performance parsing engines.

checklist

Detailed Error Reporting

Precise error messages with exact line numbers and column positions so you can fix issues quickly and accurately.

Validator Documentation

Comprehensive guide to understanding data validation concepts and best practices.

Understanding Data Validation

Data validation is a critical aspect of software development and data processing. Validating data helps ensure correctness, security, and reliability of applications:

Types of Validation

Syntactic: Checks the structure and format of the data
Semantic: Verifies that the data makes logical sense
Schema: Validates against specific schemas or standards
Well-formedness: Ensures proper structure in markup languages
Pattern Matching: Validates against specific patterns or rules

Common Validation Scenarios

API Development: Validating request/response payloads
Configuration Files: Ensuring config files are correct
Data Import: Validating imported data before processing
User Input: Checking data entered by users
CI/CD Pipelines: Automated validation of code/config

Best Practices for Data Validation

Implement effective validation with these best practices:

Client-Side vs Server-Side Validation

Client-Side: Provides immediate feedback to users
Server-Side: Ensures security and data integrity
Both: Use client-side for UX and server-side for security
Never rely solely on client-side validation for security

Handling Validation Errors

Effective error handling involves:

Providing clear, specific error messages
Indicating the exact location of errors when possible
Suggesting possible corrections
Preserving user input to avoid re-typing
Grouping related errors logically

Performance Considerations

Validate early in the processing pipeline
Use streaming validators for large data sets
Cache validation results when appropriate
Validate only what's necessary for the current operation

Common Questions

Validation checks if data is correct and follows the required syntax/rules, while formatting changes the presentation of data. A validator tells you if your JSON is valid, while a formatter makes it readable. You often need validation before formatting to ensure the data can be processed correctly.

Our basic validators check for syntactic correctness and proper structure. For schema validation (checking against specific JSON Schema, XML Schema, etc.), you would need more advanced tools. Our validators ensure the data is well-formed according to the format's basic rules.

Different validators may have slightly different implementations or accept different extensions to the JSON standard. Our validator follows the strict RFC 7159/8259 JSON specification. Common issues include trailing commas, comments (not allowed in JSON), or unquoted keys.

Yes, all validation happens entirely in your browser. No data is sent to external servers, ensuring your information remains private and secure. All processing occurs locally on your device.

Validation is limited by your browser's memory and processing power. Very large files (several MB) may cause performance issues or browser warnings. For large-scale validation, consider using command-line tools or server-side solutions.

Our validators focus on syntactic correctness rather than security vulnerabilities. They won't detect issues like potential XSS vectors or injection risks. Security scanning requires specialized tools that go beyond basic syntax validation.

Our online validators process one document at a time. For batch validation of multiple files, you would need to run each file individually or use command-line tools designed for batch processing.

Validation is crucial for preventing errors, ensuring data integrity, and maintaining security. It helps catch issues early in the development cycle, prevents malformed data from causing runtime errors, and ensures data consistency across systems. Proper validation improves overall application reliability.