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Popular Tools
Free online utilities for your daily development workflow
Text Utilities
Transform, organize, format, and clean text with powerful utilities
Hash Generator
Generate MD5, SHA-1, SHA-256, and other cryptographic hashes
Color Picker
Advanced color picker with HEX, RGB, HSL, and palette generation
Image to Base64
Convert images to Base64 format for embedding in HTML, CSS, or data URIs
Image Resizer
Resize images while maintaining aspect ratio. Perfect for logos and thumbnails
Image Cropper
Crop images with custom sizes and shapes. Supports multiple aspect ratios
QR Code & Barcode Generator
Generate customizable QR codes with colors, logos, and download options
CSV to Excel
Convert CSV files to Excel format (XLSX or XLS) with auto-sized columns
Markdown to Word
Convert Markdown (.md) files to Word documents (.docx) with formatting
API Tester
Send HTTP requests and inspect responses directly in your browser
Brain Games
Train your mind with fun and challenging puzzles
🧩 Secret Squares
Brain Challenge Game – Train logical thinking for kids from 5 years old
Designed by Thuy An
🎴 Memory Match
Flip cards to find matching pairs - Train your memory
🔢 Sudoku Master
Classic number puzzle - 4 difficulty levels
📝 Word Puzzle
Arrange letters to guess Vietnamese words - Vocabulary training
❌ Tic Tac Toe
3x3 board game with AI - 3 difficulty levels
🎨 Color Match
Remember and repeat color sequences - Memory training