Free Developer Tools

Browser-based utilities for developers. No signup, no tracking, no server-side processing.

Data Formatting

Format, validate, and transform structured data

JSON Formatter & Validator

Format, validate, and minify JSON data online. Instant syntax highlighting with error detection.

Validation

Validate URLs, emails, schemas, and more

robots.txt Tester

Test if a URL is allowed or blocked by a site's robots.txt. Validate robots.txt syntax and check crawl rules for any user-agent.

WHOIS Lookup

Look up domain registration info — registrar, creation date, expiry, nameservers, and status codes. Free and instant.

XPath Tester

Test XPath expressions against HTML or XML documents online. Preview matched nodes instantly with context.

CSS Selector Tester

Test CSS selectors against live HTML. Preview matched elements in real-time with match count and export.

Sitemap Generator

Generate XML sitemaps by crawling your website. Discover pages, validate structure, and download a ready-to-upload sitemap.xml.

SSL Certificate Checker

Check SSL/TLS certificate details for any domain — expiry date, issuer, chain validity, protocol version, and cipher suite.

Broken Link Checker

Understand how web crawlers and scraping APIs detect broken links. Learn how to identify 404 errors, redirect chains, and unreachable URLs in any website.

Page Speed Tester

Learn how web page performance is measured and how scraping APIs use performance signals to optimize data collection from slow or resource-heavy websites.

Schema Validator

Understand JSON Schema and Schema.org structured data validation. Learn how to extract and validate schema markup from web pages using a scraping API.

HTTP Debugging

Inspect HTTP headers, status codes, and responses

User Agent Parser & Detector

Detect and parse any user agent string. Identify browser, OS, device type, and bot status instantly.

HTTP Header Checker

Inspect HTTP response headers for any URL. View security headers, caching policies, CORS configuration, and server info at a glance.

Website Technology Detector

Detect the tech stack of any website. Identify frameworks, CMS, analytics, CDN, hosting, and JavaScript libraries instantly.

Security Headers Checker

Learn about HTTP security headers and how to check if a website correctly implements Content-Security-Policy, HSTS, X-Frame-Options, and other security directives.

API Tester

Learn how to test web APIs with HTTP requests — understand request methods, headers, authentication, and response handling when working with scraping APIs.

Encoding & Decoding

Base64, URL encoding, and other conversions

URL Encoder / Decoder

Encode or decode URLs and query parameters online. Handles UTF-8, special characters, and bulk processing.

SEO & Meta Tags

Analyze and validate SEO metadata and social sharing tags

Meta Tag Analyzer

Analyze SEO meta tags for any URL — title, description, Open Graph, Twitter Cards, canonical, and robots directives. Preview how your page appears on Google and social media.

Network & DNS

DNS lookups, redirect chains, and network diagnostics

Redirect Checker

Trace HTTP redirect chains and understand how 301, 302, and meta refresh redirects affect web scraping, SEO link equity, and crawl efficiency.

DNS Lookup Tool

Learn how DNS records work and how to check A, CNAME, MX, TXT, and NS records for any domain — useful for debugging web scraping connectivity issues.

Text Processing

Transform, encode, and manipulate text

Markdown Preview

Understand how web scraping APIs convert HTML content to markdown — and how to preview, validate, and optimize markdown output for LLM and documentation workflows.

Calculators

Estimate costs, rates, and performance metrics

Web Scraping Cost Calculator

Estimate the cost of your web scraping project. Calculate request volumes, anti-bot tier usage, and total API spend for price monitoring, data collection, and research workflows.