Validation & Testing Tools Page
Validate data formats, test regular expressions, and verify various input types.
Broken Link Checker
Find broken links, 404 errors, and redirects on your website. Check single pages or crawl entire sites (up to 2000 pages) with detailed reports.
Canonical URL Checker
Check if a website has proper canonical URL tags and identify potential SEO issues
Contrast Checker
Check the contrast ratio between two colors to ensure accessibility (WCAG AA/AAA) compliance. RGB values to HEX format for CSS and design.
CORS Header Checker
Check CORS (Cross-Origin Resource Sharing) headers configuration for any website or API endpoint
Credit Card Validator
Validate credit card numbers using the Luhn algorithm. Detect card type (Visa, MasterCard, American Express, etc.) and check format integrity.
CSS Validator
Validate CSS stylesheets for syntax errors, deprecated rules, and performance issues. Check for browser compatibility, optimize selectors, and ensure best practices. Perfect for front-end developers and designers.
DNS Lookup Tool
Resolve domain names to IP addresses and fetch DNS records (A, AAAA, MX, TXT, CNAME, etc.). Perfect for network diagnostics, domain analysis, and troubleshooting DNS issues.
Email Validator
Quickly check if an email address is valid. Validates email format, syntax, and provides detailed feedback on common issues.
Free HTML Validator - Check HTML Code Online (W3C Standards)
Validate HTML code against W3C standards. Find syntax errors, missing tags, and accessibility issues. Free online HTML validator for cross-browser compatibility and SEO optimization.
HTTP Header Checker
Inspect HTTP headers of a given URL request/response to debug caching, security, and SEO issues. Analyze response headers for performance optimization and security best practices.
IP Address Lookup
Look up detailed information about IP addresses including geolocation, ISP, hostname, and network details. Supports both IPv4 and IPv6 addresses with comprehensive data analysis.
JSON Validator
Validate JSON input for proper structure and syntax. Format, minify, and analyze JSON data. Perfect for debugging API payloads or configuration files.
JWT Decoder
Paste a JWT (JSON Web Token) and decode its header and payload. Useful for developers to inspect JWT contents without verification.
JWT Encoder
Create and encode JSON Web Tokens (JWT) with custom header, payload, and secret key. Perfect for developers testing JWT implementation.
Password Strength Checker
Analyze password strength in real-time based on length, complexity, entropy, and common vulnerabilities. Get detailed feedback to improve password security.
Regex Tester
Test regular expressions with sample text. Find matches, test patterns, and debug regex with real-time results and explanations.
Robots.txt Tester
Test and validate robots.txt files for crawling permissions. Check if specific URLs are allowed or disallowed for search engine bots and web crawlers. Essential for SEO optimization.
SSL Certificate Checker
Check SSL certificate details, expiration dates, and security status for any domain. Verify certificate chains, issuer information, and protocol support for comprehensive security analysis.
User Input Sanitizer Tester
Test user input strings against XSS, SQL injection, and other vulnerabilities. Validate input sanitization and security measures. Essential for web application security testing.
User-Agent Parser
Parse and analyze User-Agent strings to extract detailed information about browsers, operating systems, devices, and engines. Perfect for web analytics and debugging.
XSS Payload Tester
Test XSS payloads against various sanitization techniques and encoding methods. Analyze payload effectiveness and learn about XSS prevention strategies. Essential for security testing and education.