i4u - 60+ Free Online Tools
i4u.jp offers image editing, PDF processing, text conversion, developer tools, and more - all running in your browser. With the spirit of "for you", everything is free and ready to use.
Popular Tools
Voice T-Shirt Maker
Record your voice and create a T-shirt with waveform design. Playable via QR code
Image Format Converter
Convert image formats
Image Resizer
Resize and compress images to optimize file size
Text Diff Comparison
Compare two texts and visualize differences
JSON Formatter & Validator
Format, minify, validate, and display statistics for JSON.
Base64 Converter
Convert text or files to Base64 format and decode
PDF Merger & Splitter
Merge multiple PDF files or split a single PDF into multiple files
QR Code Generator
Convert text, URLs, WiFi settings into QR codes
Password Generator
Generate secure and strong passwords
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Latest Guides
date-calculator Complete Guide - From Basics to Advanced
A comprehensive guide to date-calculator for beginners. Learn how to use, practical examples, FAQs, and troubleshooting.
db-schema-designer Complete Guide - From Basics to Advanced
A comprehensive guide to db-schema-designer for beginners. Learn how to use, practical examples, FAQs, and troubleshooting.
dpi-converter Complete Guide - From Basics to Advanced
A comprehensive guide to dpi-converter for beginners. Learn how to use, practical examples, FAQs, and troubleshooting.