A curated collection of 50,000+ free resources, icons, cheat sheets, and TLDRs. No login, unlimited downloads.

Available Tools

• JSON Utilities
  ^{Format, validate, and lint JSON online for free with Hexmos Free DevTools. Enjoy multiple indentation options and real-time validation in an ad-free environment.}
• JSON Prettifier
  ^{Format, validate, and lint JSON online for free with Hexmos Free DevTools. Enjoy multiple indentation options and real-time validation in an ad-free environment.}
• JSON Validator
  ^{JSON Validator - Check & Validate Your JSON Online}
• JSON Fixer
  ^{JSON Fixer - Automatically Correct JSON Errors}
• Password Generator
  ^{Generate secure passwords instantly with Hexmos Free DevTools. Choose quick presets, customize password type, length, and characters for strong, random passwords.}
• Dockerfile Linter
  ^{Comprehensive Dockerfile linter. Analyze, validate, and optimize Dockerfiles for syntax errors, security risks, performance issues, and best practices.}
• Date Time Converter
  ^{Free online Date Time Converter by Hexmos. Instantly convert UTC, ISO, Unix timestamps, and more. Paste or pick a date to see all formats at once, no signup needed.}
• OpenAI Token Counter
  ^{Count OpenAI tokens instantly with our free online token counter. Calculate GPT-5, GPT-4, GPT-3.5, o1 tokens.}
• Anthropic Token Counter
  ^{Count Anthropic tokens instantly with our free online Claude token counter. Calculate Claude-3.5, Claude-3, Opus tokens.}
• Json To Csv Converter
  ^{Convert JSON data to CSV format instantly. Transform arrays of objects to spreadsheet-ready CSV files with real-time preview and advanced formatting options.}
• Image To Base64
  ^{Convert images to Base64 format instantly with our free online converter. Upload PNG, JPG, GIF, WebP images and get Base64 string, HTML img tag, CSS background code. Secure browser-based processing.}
• JWT Parser
  ^{Parse and decode JWT tokens instantly with our free online JWT parser. Decode header, payload, and signature from JSON Web Tokens with real-time validation. Secure browser-based processing.}
• YAML to JSON Converter
  ^{Convert YAML to JSON format instantly with our free online converter. Transform YAML configuration files to JSON with real-time validation and formatting. Secure browser-based processing.}
• UUID Generator
  ^{Generate secure UUIDs instantly with our free online UUID generator. Create random v4 UUIDs, timestamp-based v1 UUIDs, or special nil/max UUIDs. Bulk generation and analysis tools included.}
• SVG Viewer
  ^{View and analyze SVG files instantly with our free online SVG viewer. Upload SVG files or paste SVG code to visualize, edit, and download. Real-time preview with dimension analysis.}
• SQL Minifier
  ^{Minify SQL queries instantly with our free online SQL minifier. Remove comments, extra spaces, and optimize SQL formatting for better performance and smaller file sizes. Secure browser-based processing.}
• RGB to HEX Converter
  ^{Convert RGB color values to HEX format instantly with our free online RGB to HEX converter. Transform red, green, blue values to hexadecimal color codes with real-time preview and multiple format outputs.}
• Diff Checker
  ^{Compare text and code differences instantly with our free online diff checker. Visualize changes character by character, word by word, or line by line with advanced comparison options and unified diff export.}
• Regex Tester
  ^{Test regular expressions instantly with our free online regex tester. Validate patterns, find matches, and debug regex with real-time highlighting and detailed match information. Secure browser-based processing.}
• Query Params To JSON
  ^{Convert URL query parameters to JSON format instantly with our free online converter. Parse query strings from URLs, form data, and API endpoints into structured JSON objects with real-time validation.}
• Lorem Ipsum Generator
  ^{Generate random Lorem Ipsum placeholder text instantly with our free online generator. Create words, sentences, or paragraphs for design mockups, layouts, and content testing. Fast, customizable, and ad-free.}
• JSON to YAML Converter
  ^{Convert JSON to YAML format instantly with our free online converter. Transform JSON configuration files to YAML with real-time validation and formatting. Secure browser-based processing.}
• Hash Generator
  ^{Generate secure hashes instantly with our free online hash generator. Create SHA-256, SHA-512, MD5, PBKDF2, and HMAC hashes with customizable options for security and development needs.}
• HAR File Viewer
  ^{Analyze HTTP Archive (HAR) files instantly with our free online HAR viewer. Debug network traffic, analyze web performance, and examine HTTP requests with detailed waterfall charts and table views.}
• Env to Netlify TOML Converter
  ^{Convert .env files to Netlify TOML format instantly with our free online converter. Transform environment variables for Netlify deployment configuration with proper TOML syntax and validation.}
• CSV to JSON Converter
  ^{Convert CSV files to JSON format instantly with our free online converter. Upload CSV files or paste CSV data to transform into structured JSON objects with customizable formatting options.}
• CSS Units Converter
  ^{Convert CSS units instantly with our free online converter. Transform pixels to rem, viewport units (vw, vh, vmin, vmax), and more with real-time conversion and responsive design calculations.}
• Base64 Utilities
  ^{Encode and decode text to/from Base64 format instantly with our free online Base64 encoder/decoder. Perfect for data transmission, storage, and web development with real-time conversion.}
• Base64 Encoder
  ^{Encode text to Base64 format instantly with our free online Base64 encoder. Perfect for data transmission, storage, and web development with real-time encoding.}
• Base64 Decoder
  ^{Decode Base64 to text format instantly with our free online Base64 decoder. Perfect for data retrieval and web development with real-time decoding and error detection.}
• CSS Inliner for Email
  ^{Convert CSS styles to inline styles for email HTML instantly with our free CSS inliner. Perfect for email templates, newsletters, and ensuring cross-client compatibility with real-time conversion.}
• cURL to JavaScript Fetch
  ^{Convert cURL commands to JavaScript fetch API code instantly with our free online converter. Transform command-line HTTP requests into modern JavaScript fetch calls with real-time conversion.}
• WebP Converter
  ^{Convert images to WebP format instantly with our free online converter. Upload JPG, PNG, GIF images and convert to WebP with adjustable quality settings. Batch processing and download support included.}
• QR Code Generator
  ^{Generate QR codes instantly with our free online QR code generator. Create customizable QR codes for URLs, text, contact info, and more with adjustable error correction and scale settings.}
• Fake Data Generator
  ^{Generate realistic fake data instantly with our free online fake data generator. Create mock JSON, CSV, SQL data with customizable fields for testing, development, and prototyping.}
• Cron Expression Tester
  ^{Test and validate cron expressions instantly with our free online cron tester. Parse cron jobs, validate syntax, see next execution times, and understand cron patterns with real-time feedback.}
• XML Formatter
  ^{Format and beautify XML documents instantly with our free online XML formatter. Validate XML syntax, customize indentation, and fix malformed XML with real-time formatting and error detection.}
• Chmod Calculator
  ^{Calculate Unix file permissions instantly with our free online chmod calculator. Convert between octal, symbolic, and human-readable formats with real-time permission preview and command generation.}
• User Agent Parser
  ^{Parse and analyze user agent strings instantly with our free online user agent parser. Extract browser, operating system, device, engine, and CPU architecture information with detailed breakdown and real-time analysis.}
• MAC Address Generator
  ^{Generate random MAC addresses instantly with our free online MAC address generator. Create custom MAC addresses with prefix, separator, and case options for testing and development.}
• MAC Address Lookup
  ^{Lookup MAC address vendor information instantly with our free online MAC address lookup tool. Identify device manufacturer, organization, and network details from MAC addresses.}
• Deepseek Token Counter
  ^{Count tokens instantly for Deepseek models with Deepseek Token Counter by Hexmos. Get accurate token counts for Deepseek V2, Coder, and LLM models.}
• Llama Token Counter
  ^{Count tokens instantly for Meta Llama models with Llama Token Counter by Hexmos. Get accurate token counts for Llama 3 and Llama 2 models.}
• OpenAI Cost Calculator
  ^{Estimate API costs for all OpenAI models with OpenAI Cost Calculator by Hexmos. Enter input tokens, output tokens, and API calls to see dynamic pricing for GPT-4, GPT-4o, GPT-5, o1, o3, and more.}
• Character Count
  ^{Count characters, words, lines, and byte size instantly with Character Count Tool by Hexmos. Enter your text and get real-time statistics for code, documents, and more. Estimate API costs for all models based on your input.}
• Slugify String
  ^{Convert any string to a clean, URL-friendly slug instantly with Slugify String Tool by Hexmos. Enter your text and get a slugified output for SEO, file names, and web development.}
• More tools coming soon...

Quick Start

1. Clone the repository

   git clone https://github.com/yourusername/freedevtools.git
   cd freedevtools

2. Install dependencies

   cd frontend
   npm install

3. Run development server

   make run

Related Projects

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⭐ Star This Repository

If you find these tools helpful, please consider giving us a ⭐ star on GitHub! It helps us reach more developers who could benefit from these utilities.

Contributing

We welcome contributions! Here's how you can help:

CONTRIBUTING.md

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Made with ❤️ by the developer community

Contributors

1. lovestaco
2. RijulTP
3. LinceMathew
4. shrsv
5. Amazing-Stardom