Our Developer Tools
A suite of 45 useful online tools for developers, DevOps and sysadmins.
100% free, no login required, and run client-side where possible to protect privacy.
Network & DNS
DNS Traversal (Trace)
Traces the DNS resolution path from root servers to the authoritative name server.
Launch ToolSubnet Calculator
Calculates IP networks, CIDR masks, host ranges, and broadcast addresses.
Launch ToolHTTP Header Check
Reads all HTTP response headers of a web address and analyzes their status.
Launch ToolWHOIS & RDAP Lookup
Queries registration data, expiration date, and name servers of a domain (prefers RDAP).
Launch ToolHTTP/2 & HTTP/3 Protocol Check
Checks support for HTTP/2 and HTTP/3 (QUIC) as well as ALPN latencies.
Launch ToolWhitelisted Port Scanner
Scans 15 standard ports for open services to avoid security risks.
Launch ToolSecurity & SSL
SSL/TLS Check
Analyzes SSL/TLS certificates, certificate chains, expiration dates, and ciphers.
Launch ToolSecurity Header Check
Checks HTTP security headers (HSTS, CSP, X-Frame-Options) and provides server fixes.
Launch ToolSPF & DKIM Check
Validates SPF and DKIM records for email authentication and spam prevention.
Launch ToolCSR Generator
Generates Certificate Signing Requests (CSR) and private keys for SSL certificates.
Launch ToolMail Deliverability Suite
Performs a complete audit (SPF, DKIM, DMARC, BIMI, MX, SMTP, and DNSBL) for emails.
Launch Toolsecurity.txt Checker
Checks presence and RFC 9116 compliance of security.txt files.
Launch ToolCSP Generator & Evaluator
Analyzes Content-Security-Policy headers and suggests hardening rules.
Launch ToolDomain Health Score
Aggregates DNS, SSL, Security Headers, PageSpeed, and Email Deliverability into a single score with AI recommendations.
Launch ToolServer Config Generator
Generates Nginx configurations and Apache .htaccess rules for redirects and security headers.
Launch ToolPerformance & Speed
PageSpeed Check
Measures loading times, performance, SEO, and Core Web Vitals via Google PageSpeed Insights.
Launch Toolrobots.txt & Sitemap Checker
Analyzes robots.txt syntax, sitemap.xml structure, and tests declared URLs.
Launch ToolSocial Media Meta Preview
Simulates the display of your website on Google, Facebook, LinkedIn, and Twitter.
Launch ToolDeveloper Utilities
JSON Path Transformer
Filters and transforms JSON structures using JSONPath / Query expressions.
Launch ToolYAML ↔ JSON Converter
Losslessly converts documents between YAML and JSON formats.
Launch ToolMock Data Generator
Generates test data in JSON, SQL, or CSV based on custom schemas.
Launch ToolRegex Tester
Tests regular expressions in real-time with match highlighting and capture groups.
Launch ToolUser Agent Parser
Analyzes HTTP User-Agent strings and extracts browser, OS, and device type.
Launch ToolCron Expression Generator
Creates cron expressions visually and translates them into readable text.
Launch ToolEpoch Timestamp Converter
Converts Unix timestamps to human-readable dates and vice-versa.
Launch ToolColor Contrast Checker (WCAG)
Calculates contrast ratios between two colors according to WCAG 2.1 guidelines (AA/AAA).
Launch ToolMarkdown Preview & Lorem Ipsum
Offers a live preview for Markdown text and a customizable Lorem Ipsum generator.
Launch ToolJSON/YAML Diff & .env Validator
Compares JSON/YAML files semantically and validates .env files for completeness.
Launch ToolEncoders & Hashing
Base64 Encoder/Decoder
Encodes text into Base64 or decodes it back to plain text.
Launch ToolURL Encoder/Decoder
Encodes special characters in URLs (percent encoding) or decodes them.
Launch ToolCase Converter
Converts texts to uppercase, lowercase, camelCase, snake_case, etc.
Launch ToolEncoder/Crypto Pipeline
Chains local encode, decode, JSON, text, and SHA-256 steps into reusable recipes.
Launch ToolHash Generator & BCrypt
Creates MD5, SHA-1, SHA-256, SHA-512, PBKDF2, and server-side BCrypt hashes.
Launch ToolHex Checksum Tool
Analyzes hexadecimal strings, calculates checksums, and converts data.
Launch ToolJWT Decoder
Decodes JSON Web Tokens (JWT) and visualizes payload, header, and expiration times.
Launch ToolUUID Generator
Generates cryptographically secure Universally Unique Identifiers (UUID v4).
Launch ToolPasscode & Key Generator
Generates highly secure passwords, API keys, and cryptographic keys.
Launch ToolQR-Code Generator
Generates privacy-friendly QR codes from URL/Text, WiFi, SMS, or vCards locally on the client.
Launch ToolImage ↔ Base64 & SVG Optimizer
Converts images to Base64 data URLs and optimizes SVG code locally.
Launch Tool