Developer Tools
211 tools — generators, formatters, validators and converters for developers. Free, no signup.
Quick picks
Generators
40 toolsQR Code Generator
Generate QR codes for URLs, text, WiFi, vCards and more
URL to QR Code
Turn any website link or URL into a scannable QR code — download as PNG
Barcode Generator
Generate EAN, UPC, Code128 and other barcode formats
Favicon Generator
Generate favicons in all required sizes from one image
CSS Gradient Generator
Create beautiful CSS gradients and copy the code
UUID Generator
Generate RFC-4122 UUIDs v1/v4 instantly
GUID Generator
Generate globally unique identifiers (GUIDs)
Slug Generator
Convert any text into a URL-friendly slug
Hash Generator
Generate MD5, SHA1, SHA256, SHA512 hashes from text
MD5 Generator
Generate MD5 hash from any text or string
SHA256 Generator
Generate SHA-256 cryptographic hash from text
Password Generator
Generate strong, random passwords with custom rules
Lorem Ipsum Generator
Generate placeholder lorem ipsum text for designs
Fake Data Generator
Generate realistic fake names, emails, addresses and more
JSON Generator
Generate random JSON data from a schema template
XML Generator
Generate XML documents from structure templates
YAML Generator
Generate YAML configuration files from templates
SQL Query Generator
Generate SQL SELECT, INSERT, UPDATE, DELETE queries
Regex Generator
Generate and explain regular expressions from plain English
CSS Shadow Generator
Visually build CSS box-shadow and text-shadow values
CSS Animation Generator
Create CSS keyframe animations with a visual editor
Tailwind Class Generator
Generate Tailwind CSS utility classes from CSS properties
Open Graph Generator
Generate Open Graph meta tags for social sharing previews
Robots.txt Generator
Generate robots.txt file for search engine crawl rules
Sitemap Generator
Generate XML sitemap for any website URL
Manifest Generator
Generate web app manifest.json for PWA apps
.htaccess Generator
Generate Apache .htaccess rules for redirects and security
Meta Tag Generator
Generate HTML meta tags for SEO and social sharing
JWT Generator
Generate and sign JSON Web Tokens with custom payloads
API Mock Generator
Generate mock REST API endpoints with fake JSON responses
Color Palette Generator
Generate beautiful color palettes from a base color
SVG Shape Generator
Generate SVG shapes, icons and patterns as code
SVG Wave Generator
Generate smooth SVG waves for website sections
SVG Blob Generator
Generate organic blob shapes as SVG for backgrounds
SVG Pattern Generator
Generate seamless tiling SVG background patterns
CSS Clip Path Generator
Visually create CSS clip-path polygon and circle values
CSS Grid Generator
Visually design CSS grid layouts and copy the code
CSS Flexbox Generator
Visually design flexbox layouts and copy the CSS
CSS Transition Generator
Build CSS transitions with a live play-to-test preview
Dummy API Generator
Generate dummy REST API with CRUD endpoints instantly
Converters
34 toolsJSON to CSV
Convert JSON arrays to CSV spreadsheet format
CSV to JSON
Convert CSV spreadsheet data to JSON format
JSON to XML
Convert JSON objects to XML format
XML to JSON
Convert XML documents to JSON format
YAML to JSON
Convert YAML configuration to JSON format
JSON to YAML
Convert JSON data to YAML configuration format
HTML to JSX
Convert HTML markup to React JSX syntax
JSX to HTML
Convert React JSX code to plain HTML markup
Markdown to HTML
Convert Markdown text to HTML markup
HTML to Markdown
Convert HTML pages to clean Markdown format
CSS to Tailwind
Convert regular CSS properties to Tailwind utility classes
HEX to RGB
Convert HEX color codes to RGB values
RGB to HEX
Convert RGB color values to HEX color codes
RGB to HSL
Convert RGB color values to HSL format
Base64 Encode
Encode text or files to Base64 string
Base64 Decode
Decode Base64 string back to plain text or file
URL Encode
Encode special characters in URLs (percent encoding)
URL Decode
Decode percent-encoded URL strings to plain text
JWT Decoder
Decode and inspect JWT token header and payload
Unix Timestamp Converter
Convert Unix timestamps to human-readable dates and back
Text to Binary
Convert plain text to binary code (0s and 1s)
Binary to Text
Convert binary code back to readable text
Image to Base64
Convert images to Base64 encoded data URI strings
SQL to Prisma
Convert SQL CREATE TABLE statements to Prisma schema
cURL to Fetch
Convert cURL commands to JavaScript fetch() code
cURL to Axios
Convert cURL commands to Axios request code
JSON to TypeScript
Generate TypeScript interfaces from JSON objects
JSON to Dart
Generate Dart model classes from JSON data
JSON to Go Struct
Generate Go struct definitions from JSON data
JSON to Java Class
Generate Java POJO classes from JSON objects
JSON to CSV File
Convert and download JSON data as a CSV file
ICO Converter
Convert PNG or JPG images to ICO favicon format
SVG to PNG
Convert SVG vector graphics to PNG raster images
PNG to SVG
Trace PNG images and convert to SVG vector format
Formatters
18 toolsJSON Formatter
Prettify and format JSON with syntax highlighting
SQL Formatter
Format and beautify SQL queries for readability
XML Formatter
Format and indent XML documents with proper structure
HTML Formatter
Beautify and indent HTML markup for readability
CSS Formatter
Format and beautify CSS stylesheets
JavaScript Formatter
Format and prettify JavaScript code with Prettier
TypeScript Formatter
Format and prettify TypeScript code with Prettier
Markdown Formatter
Format and normalize Markdown documents
YAML Formatter
Format and validate YAML configuration files
HTML Minifier
Remove whitespace and comments from HTML to reduce size
CSS Minifier
Minify CSS stylesheets to reduce file size
JavaScript Minifier
Minify JavaScript code to reduce bundle size
JSON Minifier
Remove whitespace from JSON to minimize file size
SVG Minifier
Minify SVG files by removing redundant attributes
XML Minifier
Minify XML documents by removing whitespace
HTML Minifier
Minify HTML code by removing whitespace, comments and redundant attributes
CSS Minifier
Minify CSS code to reduce file size and improve page load speed
JavaScript Minifier
Minify JavaScript code by removing whitespace and shortening variable names
Validators
11 toolsJSON Validator
Validate JSON syntax and structure with detailed errors
XML Validator
Validate XML documents against schema or DTD
YAML Validator
Validate YAML files for syntax errors
HTML Validator
Validate HTML markup for W3C compliance
CSS Validator
Validate CSS stylesheets for errors and browser support
JavaScript Validator
Lint and validate JavaScript code for syntax errors
Email Validator
Validate email address format and domain existence
Regex Tester
Test and debug regular expressions with live match preview
JWT Validator
Validate and verify JSON Web Token signatures
Schema Validator
Validate JSON data against a JSON Schema definition
API Response Validator
Validate API JSON responses against expected schemas
Image Tools
19 toolsSVG Optimizer
Reduce SVG file size by removing unnecessary code
URL to Screenshot
Capture a full-page screenshot of any website
Image Comparison
Compare two images side by side with a slider
Mockup Generator
Place your design on device mockups (phone, laptop, etc.)
Image to CSS Background
Convert image to CSS background-image with Base64
Image Compressor
Compress images for web with quality control
Image Resizer
Resize images to exact pixel dimensions
Image Cropper
Crop images to any size or aspect ratio
SVG Editor
Edit SVG files with a visual code editor
SVG Compressor
Compress SVG files by removing metadata and whitespace
Website Screenshot Tool
Take full-page screenshots of any website URL
Device Mockup Tool
Place screenshots on phone and laptop device frames for developers
Browser Mockup Generator
Wrap designs in a browser chrome frame for presentations
Favicon Extractor
Extract and download favicon from any website
Color Extractor
Extract dominant color palette from any image
Blur Image Tool
Add Gaussian blur effect to images
Pixelate Image Tool
Apply pixelation effect to images for privacy
Remove Background
AI-powered background removal from images
AI Image Upscaler
Upscale low-resolution images with AI
API Tools
10 toolsAPI Tester
Test REST API endpoints with GET, POST, PUT, DELETE
REST Client
Full-featured REST API client with headers and body
GraphQL Playground
Explore and test GraphQL APIs with an interactive editor
Webhook Tester
Get a temporary webhook URL to inspect incoming requests
API Response Viewer
Visualize and explore API JSON responses in a tree view
API Status Checker
Check if an API endpoint is live and measure response time
Request Header Viewer
Inspect HTTP request headers sent by your browser
HTTP Status Code Lookup
Look up meaning and description of any HTTP status code
Postman Collection Viewer
Import and browse Postman collection files
API Mock Server
Create a live mock API server with custom responses
Text & Color
7 toolsHTML Entity Encoder
Encode special characters to HTML entities
HTML Entity Decoder
Decode HTML entities back to readable characters
Color Picker
Pick colors and get HEX, RGB, HSL values instantly
Gradient Picker
Create multi-stop gradients and get the CSS code
Contrast Checker
Check color contrast ratio for WCAG accessibility compliance
Tailwind Color Generator
Generate custom Tailwind CSS color scales from any base color
Material Color Generator
Generate Material Design color palettes from a primary color
Database
7 toolsSQL Beautifier
Beautify and format SQL queries with custom indentation
SQL Minifier
Minify SQL queries by removing whitespace and comments
SQL Query Runner
Run SQL queries against an in-browser SQLite database
MongoDB Query Generator
Generate MongoDB queries from plain English descriptions
Prisma Schema Generator
Generate Prisma schema from existing database structure
ER Diagram Generator
Generate entity-relationship diagrams from schema input
DB Schema Viewer
Visualize and browse database schema structure
Security
8 toolsPassword Strength Checker
Check password strength and get improvement suggestions
Bcrypt Generator
Hash passwords with bcrypt and verify hash matches
JWT Encoder
Create and sign JWT tokens with custom claims
SSL Checker
Check SSL certificate validity, expiry and chain
CORS Tester
Test CORS headers and cross-origin request policies
CSP Generator
Generate Content Security Policy headers for your site
Secure Header Checker
Audit HTTP security headers of any website
Token Generator
Generate secure random tokens and API keys
SEO Tools
13 toolsSEO Analyzer Pro — by siteIQ
Full-scale SEO audit — meta tags, Core Web Vitals, backlinks, keywords, structured data & more. Powered by siteIQ, our in-house website intelligence platform.
Meta Tag Checker
Analyze meta tags of any URL for SEO optimization
Open Graph Preview
Preview how a URL looks when shared on social media
Twitter Card Preview
Preview how a URL appears on Twitter/X cards
Robots.txt Tester
Test robots.txt rules for specific user agents and URLs
Sitemap Validator
Validate XML sitemaps for errors and proper structure
Keyword Density Checker
Analyze keyword frequency and density in page content
SERP Snippet Preview
Preview how your page appears in Google search results
Meta Description Generator
Generate SEO-optimized meta descriptions for any page with AI
SEO Title Generator
Generate click-worthy SEO page titles with AI
Keyword Extractor
Extract primary and secondary keywords from any text content
Keyword Grouping Tool
Group related keywords into semantic clusters with AI
AI SEO Writer
Write fully SEO-optimized blog posts and articles with AI
Web Tools
11 toolsDNS Lookup
Look up DNS records (A, AAAA, MX, TXT, CNAME) for any domain
WHOIS Lookup
Look up domain registration and ownership information
IP Lookup
Look up geolocation and ISP info for any IP address
User Agent Parser
Parse user agent strings to detect browser and OS
HTTP Header Checker
Inspect HTTP response headers from any URL
Redirect Checker
Trace HTTP redirect chains for any URL
Ping Tool
Ping any host or IP address to check reachability
PageSpeed Insights
Full Google Lighthouse + Core Web Vitals report — scores, real-user field data & screenshot
Website Speed Checker
Real Lighthouse performance report — scores, metrics & screenshot (mobile + desktop)
Core Web Vitals Checker
Real LCP, INP & CLS from Chrome UX field data + full Lighthouse lab audit
npm Package Size Checker
Check the minified + gzipped size and dependency count of any npm package (via Bundlephobia)
DevOps
7 toolsDockerfile Generator
Generate optimized Dockerfiles for any language/framework
Kubernetes YAML Generator
Generate Kubernetes deployment, service and ingress YAML
ENV File Generator
Generate .env files from a list of variable definitions
Cron Expression Generator
Build cron expressions with a visual time selector
Cron Tester
Test cron expressions and see next execution times
NGINX Config Generator
Generate NGINX server block configurations
GitHub Actions Generator
Generate GitHub Actions CI/CD workflow YAML files
AI Dev Tools
9 toolsAI Code Generator
Generate code in any language from plain English prompts
AI Regex Generator
Generate regular expressions from plain English descriptions
AI SQL Generator
Generate SQL queries from plain English questions
AI Commit Message Generator
Generate descriptive git commit messages from code diffs
AI README Generator
Generate professional README.md files for any project
AI API Documentation Generator
Generate API documentation from code or endpoints
AI Test Case Generator
Generate unit test cases from function definitions with AI
AI Bug Explainer
Paste buggy code and get a clear explanation of the issue
AI Error Debugger
Paste error messages and get step-by-step fix instructions
Frontend & More
17 toolsBulk Image Rename
Rename multiple images at once with patterns, numbering, and prefixes
Code Editor Pro
Full VS Code-like browser editor — HTML/CSS/JS live preview, Python, TypeScript, console output & multi-file projects.
React Component Generator
Generate React functional components from descriptions
Tailwind Component Generator
Generate Tailwind CSS UI components from descriptions
JSX Formatter
Format and prettify React JSX code
React Hook Generator
Generate custom React hooks from use-case descriptions
Next.js Route Generator
Generate Next.js App Router page and API route files
TS Interface Generator
Generate TypeScript interfaces from JSON or descriptions
Type Generator
Generate TypeScript types and union types
Enum Generator
Generate TypeScript and Java enum definitions
Zod Schema Generator
Generate Zod validation schemas from TypeScript types
Markdown Previewer
Live preview Markdown with syntax highlighting
Markdown Editor
Full-featured Markdown editor with live preview
Markdown Table Generator
Generate Markdown tables visually
README Generator
Create structured README.md files with templates
File Name Cleaner
Batch clean filenames by removing special characters
Folder Tree Generator
Generate ASCII folder tree diagrams for documentation
About Developer Tools
ToolHub’s developer tools cover the small utilities every developer reaches for constantly — UUID/GUID generators, hash generators, password generators, JSON/XML/YAML formatters and validators, regex builders, SQL query generators, and CSS/Tailwind generators — all free, online, no signup.
Beyond the basics, AI-powered tools like the AI Code Generator, AI Regex Generator and AI Commit Message Generator turn plain-English descriptions into working code, saving time on boilerplate and repetitive syntax lookup.
These tools are built for quick, one-off tasks during development — generating a UUID for a test fixture, formatting a messy JSON payload, checking a regex pattern, or generating placeholder data for a demo — without needing to install a package or spin up a script.
Frequently asked questions
Are ToolHub developer tools really free?
Yes — generators, formatters, validators and converters are free with no signup. A small set of AI-powered tools are marked Pro.
Can I generate test/fake data for development?
Yes — the Fake Data Generator and JSON/XML/YAML Generators create realistic placeholder data from templates, useful for testing and demos.
Do you have API testing tools?
Yes — the API category includes request testers, response formatters and related utilities for working with REST APIs during development.
What formats do the formatter tools support?
JSON, XML, YAML, SQL, CSS and more — each formatter validates and pretty-prints the input, with minify options where relevant.
Can AI generate code or regex for me?
Yes — AI Code Generator, AI Regex Generator and AI SQL Generator turn plain-English descriptions into working code, regex patterns or SQL queries.